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study programme
Faculty: CEITECAbbreviation: CEITEC-AMN-EN-PAcad. year: 2022/2023
Type of study programme: Doctoral
Study programme code: P0588D110003
Degree awarded: Ph.D.
Language of instruction: English
Accreditation: 26.4.2021 - 26.4.2031
Mode of study
Full-time study
Standard study length
4 years
Programme supervisor
prof. RNDr. Radim Chmelík, Ph.D.
Doctoral Board
Chairman :prof. RNDr. Radim Chmelík, Ph.D.Vice-chairman :prof. Ing. Radimír Vrba, CSc.Councillor internal :prof. RNDr. Josef Jančář, CSc.prof. RNDr. Tomáš Šikola, CSc.doc. Ing. Miroslav Kolíbal, Ph.D.prof. RNDr. Karel Maca, Dr.Councillor external :prof. RNDr. Ludvík Kunz, CSc., dr. h. c.prof. RNDr. Václav Holý, CSc.prof. RNDr. Jiří Pinkas, Ph.D.
Fields of education
Issued topics of Doctoral Study Program
The goal of the project is a design of LCP and suitable photonic dopants causing local conformational changes in the LCP network resulting in local deformation and preparation of block copolymer/quantum dots nanocomposites, developing suitable deposition technique of these systems into photonic networks on a solid substrate and testing of the light stimulated mechanoadaptability of the model systems.
Tutor: Jančář Josef, prof. RNDr., CSc.
The water resources play an important role in human life as the it is a vital for human being and also the foodstuff derivated from plants or animal require water. Therefore, it is essential to continuously monitor the possible contamination of water resources using the in situ sensing devices. Electrochemical methods are very robust for qualitative and quantitative analysis of liquids. Thanks to their inherent features such as high sensitivity, and cost effectiveness, electrochemical sensors offer a promising tools for the in-situ online monitoring of the water contaminants. We have proofed electrochemical methods for detection and quantification of various water contaminants such as heavy metals, fungicide and pesticides. Analysis performed in laboratories is routine today and its transfer to autonomous systems seems easy. However, to create smart systems needs complex approach to enable the remote monitoring, integrate electrochemical sensing functionality, power management, communication, process the electrochemical signal, analyse the results and convert them to a concentration. The smart system approaches in analyser-based system has to fulfil good sensitive analysis, low inaccuracy, smart functionalities and low cost in one system. Moreover, the system should be able to justify if the obtained concentration of the specific contaminant is within the safety level. If the concentration of a contaminant exceeds the threshold concentration, the designed smart system will activate the warning alarm to inform whom may be concerned.
Tutor: Hubálek Jaromír, prof. Ing., Ph.D.
Project will focus on lightweight engineering materials fabricated by hierarchical assembly of building blocks into prescribed local architectures yielding unprecedent combination of stiffness, strength , toughness, impact resistance at low density and novel acoustic properties. Fundamental components investigated will include block copolymers and their nano-composites with controlled nanoparticle spatial organization.
Manufacturing industries are always seeking to improve techniques to lower cost, energy and expand their capability. Additive manufacturing (AM) is rapidly growing and bringing novel possibilities to expand manufacturing capability. On the other hand, traditional manufacturing refers to long-established manufacturing methods, quality assured and implemented in the commercial space. The capability of AM in many cases already replace the established traditional manufacturing methods. This work deals with an implementation of AM in to X-ray computed tomography regions which deals with development of special sample holders, in-situ tools, and reference objects for metrology. All these require a light, rigid and special shaped parts which AM can generate. Moreover, absorption properties of material and stability of the mechanical properties in X-ray radiation must be considered.
Tutor: Kaiser Jozef, prof. Ing., Ph.D.
This doctoral topic explores material extrusion and vat polymerization for the additive manufacturing of titanium porous structures with applications such as tissue engineering scaffolds, bone implants and catalytic supports. The research involves the development of new titanium formulations for use in additive manufacturing, topology optimization, sintering and characterization of the mechanical, chemical and biological performance. Along the studies, the candidate will have the opportunity to learn and work from the synthesis to the characterization of the materials. Highly motivated and collaborative candidates with outstanding track of records and with the ambition to learn from both materials and biological sciences are welcome to submit an application.
Tutor: Montufar Jimenez Edgar Benjamin, M.Sc., Ph.D.
The aim of the work will be the preparation and characterization of new hydrogel biomaterials, which will be subsequently modified by bioactive core-shell nanoparticles. The release of bioactive components and their activity in terms of biological effectiveness for targeted applications will be monitored. The samples will be characterized in terms of biodegradation in physiological conditions, mechanical properties and morphology. Furthermore, their biological effectiveness, including cytotoxic and antibacterial properties, will be evaluated.
Tutor: Vojtová Lucy, doc. Ing., Ph.D.
Laser-Induced Breakdown Spectroscopy (LIBS) is a technique providing fast analysis of investigated sample surface. Its performance is oriented on repetition rate and thus enable elemental imaging of large-scale areas. Currently, the LIBS analysis has resolution on the level of hundreds of microns which is not sufficient for high-end applications, especially in biology. The goal of this thesis is to design a LIBS system with high spatial resolution with satisfactory sensitivity in detection of selected analytes.
Multifunctional advanced ceramic materials exhibit a proper synergy of mechanical, optical, electrical or magnetic properties. The processing of such materials requires the optimization of all steps of the ceramic technology, i.e. the treatment of the input powder precursors and the selection of suitable methods of their shaping and sintering. The aim of the dissertation work will be the utilization of modern ceramic technology methods (dry and wet forming methods, pressure-less and pressure-assisted sintering) to prepare multifunctional ceramic materials and composites and evaluate their microstructure and properties in relation to possible applications. The work will be supported by ongoing projects of the supervisor such as "Development of functional ceramic and glass ceramic materials in collaboration with the Center of Excellence FunGlass", "Microstructure and functional properties refinement by dopant distribution in transparent ceramics - combined experimental and theoretical approach", "Tailoring of interfaces in lead-free ferroelectric-dielecric composites to enhance their electromechanical properties “.
Tutor: Maca Karel, prof. RNDr., Dr.
X-ray computed tomography (CT) is one of the most powerful methods for 3D visualization and inspection. This non-destructive method especially provides sufficient resolution and contrast to evaluate any microstructural features, with the ability to resolve structures even below one micron. The complete information about any biological sample, from macroscale to nanoscale, can be then easily acquired in non-destructive manner and thus enabling the visualization and the quantification of cellular features and intracellular spaces opening the way for virtual histology, live cell and subcellular imaging and correlative microscopy. This work addresses the practical implementation of lab-based CT systems with high-resolution for imaging and mainly 3D characterization of biological structures by development of dedicated sample preparation and CT measurement methodologies together with testing and evaluation of possibilities of advanced CT techniques such as phase-contrast imaging CT or dual-energy CT for those applications.
The nanostructured surfaces show antibacterial properties. To harness these properties, it is necessary to develop a methodology for large-scale production of nanostructures on objects of various shapes, surfaces of which are far from ideal. Our preliminary data show that the electron beam can be used to grow polymeric nanostructure on surfaces of ceramics. To extend the basic knowledge to applications, it is necessary to describe and understand the role of growth parameters, quality of the substrate, chemistry of employed precursor, etc. In parallel, the properties of fabricated nanostructures should be assessed. The goal of Ph.D. is to grow arrays of nanostructures and assess the role of the growth parameters on their morphology, mechanical, chemical, and antibacterial properties. Our vision is to develop a scalable methodology for nanostructured coatings of implants, which would prevent post-surgery inflammation and facilitate the healing process. (For detailed information, please, directly contact Jan Čechal or David Salamon)
Tutor: Čechal Jan, prof. Ing., Ph.D.
The project is focused on bringing an anti-bacterial and anti-viral functionality to the parylene coating. The different technological approaches will be studied including co-deposition (semi-bulk properties) of anti-microbial nanoparticles (NPs) with parylene to develop NPs/Parylene composite, ALD technique or grafting of anti-microbial molecules (near surface). The control anti-microbial efficiency over time and biocompatibility will be challenging. Besides, fabrication and characterization of the functional parylene film with micro/nano hierarchical structures will be developed, and tested against bacteria and viruses.
Tutor: Fohlerová Zdenka, doc. Mgr., Ph.D.
Molecular magnets and modern solid-state materials are considered as the building blocks of future quantum technology. The influence of the substrate on the magnetic properties of molecular magnets is crucial for molecular-scale technology like magnetic memory and single molecule transistor. This Ph.D. project will focus on the magneto-optical studies of molecular magnets, modern solid-state materials as well as on the spin-substrate coupling with different solid surfaces by means of High Frequency Electron Paramagnetic Resonance (HF-EPR) and Fourier Transform Infrared (FTIR) spectroscopy. The student will be involved in characterization of these materials by these spectroscopical methods as well as by a wide range of surface probes accessible in the CEITEC (XPS, SEM, etc.). The objective of this project is to be able to predict and evaluate magnetic properties of such materials/structures and provide the right theoretical description of experimental results. This objective includes the improvement of EPR and FTIR techniques in term of standing waves in Zeeman maps. The student will work in close collaboration with the internal and external scientists.
Tutor: Neugebauer Petr, doc. Dr. Ing., Ph.D.
Quantum computers are currently applied in an ever-growing number of scientific and engineering research areas. Their onset is foreseen also in theoretical calculations in computational materials science. The prime topic of this PhD study will be to use currently available quantum computers and their simulations in a theoretical study of materials. The secondary topic will be to develop a suitable software tools for applications in the case of quantum computing technologies and systems.
Tutor: Friák Martin, Mgr., Ph.D.
The highly-engineerable scattering properties of metallic and high-index semiconductor/dielectric nanostructures currently underpin the operation of nowadays metasurfaces. They support geometrical plasmonic or Mie resonances that offer strong light-matter interaction and excellent control over the scattering phase and amplitude. Their optical responses tend to be of a simple, linear form and they are hard to modify with external stimuli. As a result, basic Maxwell equation solvers can be used to predict and optimize their behavior. In stark contrast, van der Waals (vdW) materials comprised of atomically-thin layers bonded by the vdW force exhibit a fascinating diversity of quantum, collective, topological, non-linear, and ultrafast behaviors. It is exciting to think how such materials may open up new functions for metasurfaces [1]. This PhD topic aims to start addressing that question by exploring the new fundamental physics that can emerge at the cross roads of the metasurface and vdW fields. We will start by exploring how the properties of two-dimensional (2D) vdW semiconductors materials, such as the transition metal dichalcogenides (TMDCs), can be modified by subwavelength patterning to form atomically-thin metasurfaces. Further, flat 2D-material based metasurface optical devices for dynamic wavefront control providing new functionalities not achievable by bulk optical elements or “classical” plasmonic or all-dielectric metasurfaces will be studied. References: [1] J. van de Groep et al., Exciton resonance tuning of an atomically thin lens, Nature Photonics 14, 426–430 (2020).
Tutor: Šikola Tomáš, prof. RNDr., CSc.
Proposed doctoral thesis will be focused on the research in the field of biodegradable polymeric materials based on thermoplastic starch, polymeric blends with TPS and composites of TPS reinforced with cost-effective nature materials derived from food industry as by-products. The aim is the optimization of the composition of TPS/biodegradable matrice-filler system with respect to mechanical properties, processability, biodegradability, hydrophobic/hydrophilic behaviour etc. Rheological analysis will be the key tool for the optimization of the polymeric blends with optimal material properties suitable for conventional plastics processing technology and testing for application in single use disposable products according to CZ and EU legislation.
Tutor: Kučera František, Mgr., Ph.D.
Hydrogels are water-insoluble 3D networks of polymer chains capable of holding large amounts of water. They are irreplaceable as contact lenses or wound dressings. However, their application field is wider, including tissue replacements or drug delivery system with controlled drug release. Hydrogel properties can be combined with fast developing area of plasma activated liquids. It was shown that plasma produces a coctail of reactive oxygen and nitrogen species that have positive effects, e.g., on plant growth or anticancer therapies. These effects are increased when using hydrogels as they are more stable than liquids, i.e., able to keep reactive species for longer time. The aim of this thesis is to design, prepare and optimize different types of plasma activated hydrogels based on natural products (cellulose, collagen, lignin) applicable as 3D models of skin or vessels, drug delivery systems, wound dressings or in artificial tissues.
Tutor: Zajíčková Lenka, doc. Mgr., Ph.D.
Electrical stimulation is a fundamental approach for neuroscience. It relies on pulsed electric fields acting on voltage-gated ion channels. This project will explore an entirely different way to modulate channel function and neuronal excitability: electrochemistry. The research target is dorsal root ganglion (DRG) neurons. The idea is to use direct current to drive oxygen reduction, yielding localized production of hydrogen peroxide, and thus triggering responses in ion channels. Testing this requires merging biophysics, electronic engineering, and pain research. We will target two types of peroxide-sensitive channels, one for stimulating neural activity, and the other for downregulating it: transient receptor vanilloid channels; and voltage-gated potassium channels, respectively. We will scrutinize activation using cultured cells, dissociated DRG neurons, and in vivo. We will microfabricate custom electrodes to probe unanswered questions about the role of hydrogen peroxide in pain transduction. We hypothesize that electrically-controlled peroxide delivery may block pain, and may provide a novel method to treat chronic pain.
Tutor: Glowacki Eric Daniel, prof., Ph.D.
For maximum information yield about live cells behaviour provided by coherence controlled holographic microscopy it is inevitable to design and develop complex automated bioreactor. Such a device should ensure optically suitable accommodation of live cells in the microscope with provision of control over physiological microenvironment and preprogrammed challenges. The task is to design, develop and validate the complex automated biorector for T1 holographic microscope.
Tutor: Veselý Pavel, MUDr., CSc.
Nowadays, the excessive use of pharmaceutical products and dyes due to the entry of some of these compounds into the environment has raised concerns worldwide. In recent years, without any restrictions, these materials have been discharged continuously to the environment. Although their entry into aquatic environments may be low, their continuous navigation due to the cumulative effect can be considered a potential risk to aquatic ecosystems and their microorganisms. The presence of these drugs in the environment leads to the ecological toxicity and development of antibiotic-resistant pathogens that potentially threaten ecosystem function and human health. Carbon family materials are known for their tremendous adsorption capacity due to their high porosity and their electrostatic interaction with adsorbate. The use of graphene oxide is highly regarded in adsorption processes. Graphene oxide is considered a suitable inexpensive adsorbent due to its ease of access, ion exchangeability, and unique physicochemical properties.
Tutor: Richtera Lukáš, doc. RNDr., Ph.D.
Nanotechnology has been promoting the development of ultrasensitive detection of biomarkers on diverse platforms including chromatic, electrochemical, chemiluminescent, and fluorescent assays for decades. The realization of rapid onsite point-of-care bioassays is highly desired particularly for applications in agriculture, environmental monitoring, and disease diagnosis. The successful detection of a biomarker relies on the efficiency of both the biorecognition of the analyte and the signal transduction. Nanozymes are nanomaterials that possess enzyme-like characteristics. These artificial enzymes have attracted a lot of attention in various applications. Natural enzymes are mostly composed of proteins made from amino acids and can be easily denatured due to environmental conditions, leading to an inactive state. Furthermore, their preparation, purification, and storage are quite difficult, time-consuming, and expensive. However, nano-sized enzyme mimics have advantages of high stability as well as large-scale synthesis, cost-effectivity, size and shape controllability, and ease of preparation and purification.
The Compositionally- Complex Ceramics (CCCs) are class of medium- to high-entropy ceramics, which can alternatively and equivalently be named as Multi-Principal Cation Ceramics (MPCCs). Their typical composition is based on a single-phase ceramic solid solutions with at least three principal (meaning typically 5%-35%) cations, for example (Hf1/3Zr1/3Ce1/3)1-x(Y1/2X1/2)xO2-δ where X=Yb, Ca, and Gd, respectively, and x=0.4, 0.148, and 0.058. Since 2015 also the other type of CCCs such as borides, carbides and silicides are known. These special types of ceramics possess a high entropy, which has a large consequence on its mechanical, thermal and other properties. The topic of this thesis will be in the finding of the right compositions, preparation of CCCs as well as the evaluation of the achieved properties.
Tutor: Pouchlý Václav, doc. Ing., Ph.D., Ing.Paed.IGIP
III-nitrides (Ga,Al,In-N) are direct wide-bandgap semiconductors in which atoms are held together by ionic and covalent forces. We have recently developed an empirical model for GaN with self-consistent charge transfer, which treats ionicity at the same footing with covalency. The objective of this project is to utilize this new model to investigate the structures and charge transfer around extended defects in GaN and AlN using the methods of molecular statics and dynamics. In the second part of the project, this method will be applied to study interfaces between hexagonal AlN and Si{111} as well as between cubic GaN and Si{100}. New knowledge from these simulations will be immediately correlated with another project currently running in the group, which focuses on optimization of the early stage of epitaxial growth of III-nitride films.
Tutor: Gröger Roman, doc. Ing., Ph.D. et Ph.D.
The immune system and the skeletal system evolved together in vertebrates. Therefore there is a close and synergic relationship between them. The aim of the project is to study in vitro the crosstalk between immune and bone cells to learn how the physicochemical and structural properties of materials can control such interactions in order to develop new therapies for blood and skeletal diseases. Along the studies, the candidate will have the opportunity to learn and work from the synthesis of the materials to the biological characterization. Highly motivated and collaborative candidates with outstanding track of records and with the ambition to learn from both materials and biological sciences are welcome to submit an application.
Proposed PhD project is oriented on the synthesis and characterization of magnetically active transition metal and/or lanthanide complexes showing specific magnetic phenomena like spin crossover effect, single molecule magnetism or single chain magnetism. Such coordination compounds exhibit magnetic bi- or multistability and in this sense are very attractive from the application point of view. Possible technological utilization might be in the case of high capacity memory devices, display technologies, spinotronics, contrast agents for magnetic resonance imaging etc. PhD study will be focused on the advanced organic and coordination synthesis of mononuclear and polynuclear complexes of transition metals and/or lanthanides. New-prepared compounds will be characterized by analytical and spectral methods and magnetic properties will be studied by means MPMS SQUID.
X-ray computed tomography (CT) is an important method for 3D non-destructive imaging of samples in many fields. It is commonly used in industry for defect detection and quality control, scientific projects utilise imaging and quantification of data and apply a number of analyses to determine morphological and physical parameters. To put CT data in context with other methods, they often have to be supplemented with established imaging methods such as electron and light microscopy and qualitative techniques such as X-ray spectroscopy. The data from each technique typically have a different format, size, resolution, etc. Combining such different information about samples is a challenge. When correlating two different 3D datasets, it is necessary to ensure that the sample structures correspond to each other. For a combination of 2D and 3D techniques, a corresponding 2D section has to be found in the 3D dataset. This requires a programming approach or a use of special software. The work will deal with techniques of correlation of information from various imaging methods. Such a multidisciplinary approach is in high demand today and has a big potential.
Properties of multifunctional magnetic materials are closely linked to the subtle interplay of different order parameters. The thesis aims at combining electron diffraction techniques with different depth sensitivity to investigate the relation between structural and magnetic order in complex materials. The project assumes previous practical experience with electron microscopy.
Tutor: Uhlíř Vojtěch, Ing., Ph.D.
Engineering and production of novel materials, including coatings and layers, is demanding new analytical solutions. Compared to other analytical techniques, Laser-Induced Breakdown Spectroscopy (LIBS) enables selective ablation of layers with variable depth resolution. However, the depth of the analysis with certain number of laser pulses differs for individual materials. The calibration of depth to laser pulse number is also of an issue, while there is no solid evidence for this phenomenon in classical LIBS literature. The goal of this thesis is to find complementary approaches, for instance using Computed Tomography and standard approaches of metallography, in depth profiling in order to fully calibrate LIBS technique to depth profile analysis. As an output, methodological protocol applicable across broad range of materials is demanded.
The aim of the thesis will be the design of 3D nanostructured materials with the aid of the new method. The principle is a preparation of the 3D structures by stacking of very thin layers. The collection of the layers will create a 3D pattern that can show functional properties. These materials can be structured similarly to natural materials, for example, a cell membrane-like structure. Other materials may exhibit controlled release of active molecular compounds for medical applications such as capsaicin. The student's task will be to cooperate in the development of this method. Next, his/her task will be the designing of his/her own systems which can be created by this method. The topic is proposed in the framework of the TAR project and is in cooperation with the Vietnamese Academy of Sciences. (The student can but will not be obliged to travel to Vietnam, other international cooperation and travel will be also appreciated and supported.)
Tutor: Žídek Jan, Mgr., Ph.D.
Plastic materials are intensively polluting our environment. They are getting into the food chain and influencing individual bio-organisms in the form of microplastics. Their toxicity and impact on living organisms, thus, must be assessed. The topic of this thesis is to find an integrative approach to study the fate and effects of emerging microplastics in the aquatic environment. Main goal is to find methodology for analysis of microplastics accumulated in aquatic organisms in order to understand adverse outcomes.
Nowadays, nanoparticles are produced in a variety of sizes, shapes and compositions specifically engineered to meet the needs of individual applications (e.g., specific labels of proteins in cancer research). Their enormous production is, however, related to their spread in the environment causing pollution and affecting living organisms. This thesis aims the detection of nanoparticles in soft tissues as characteristic nanometallic labels and in hard tissues as potentially toxic pollutants. This broader scope envisions to prove the performance of LIBS as an alternative to standard fluorescent techniques with multiplexing capability and to provide a platform for understanding the fate of nanoparticles in organisms.
Tutor: Pořízka Pavel, doc. Ing., Ph.D.
Pulsed Electron Paramagnetic Resonance (EPR) methods are intensively used to investigated structure and dynamics of complex macromolecules containing unpaired electrons. Among these methods Pulsed Electron-Electron Double Resonance (PELDOR) also known as Double Electron-Electron Resonance (DEER) has emerged as a powerful technique to determine relative orientation and distance between macromolecular structural units on nanometre scale. For successful applications of pulsed EPR methods it is important to have tools enabling transformation of measured signals into structural information. The goal of this PhD project is to develop new effective computational procedures and computer programs for the processing of measured pulsed EPR data in order to extract structural and dynamical information from experiments. This goal also includes application of the developed computational methods to real experimental data obtained on the molecules tagged with spin labels. For more details please contact Petr Neugebauer.
Exploring advanced porous materials is of critical importance in the development of science and technology due to their unique characteristics and specific applications. Porous membrane with precise positioning of pores must be prepared by microfabrication instead of conventional track-etching. Parylene or PDMS microfabrication processing is not trivial and the related technological development is not as far developed as for rigid materials such as silicon, oxides, nitrides and metals. Moreover, patterning polymeric materials with features smaller than 5μm in a reproducible and reliable way is still cumbersome. Additionally, the application of polymeric porous membrane as the transducer in sensing applications has been found to be highly desired. Therefore, the aim of the project is the development of flow-through impedance sensor based on the porous polymeric membrane for the biomolecule detections. Membranes with different geometries will be produced. Membrane fabrication and electrode deposition processes will be optimized and characterized. The project will also include modification of the pores for the immobilization of the biorecognition component and the detection of biomolecules itself.
As known the electrochemical biosensors offer several advantages in clinical and medicinal analysis that include rapid measurement, being inexpensive and simple to operate. Moreover, they are attracting more attention in biochemical and biological studies where the identification and the quantification of the transients and compounds released from the cells under different conditions is desired. Therefore, the miniaturization of the electrochemical biosensors even enables more applications for them in in vivo analysis where there are not so many other analytical methods which can be applied. Herein, within the PhD study, the student will work on fabrication of the microbiosensor by an appropriate modification of the carbon fiber trapped in glass capillary and further application in in vivo analysis.
The amount of data obtained in one experiment is steadily increasing. Contemporary state-of-the-art Laser-Induced Breakdown Spectroscopy system provide bulky data sets with millions of objects (spectra) and thousands of variables (wavelengths). Thus, there is a must driven by more efficient data storage, handling and processing; this might be tackled by lowering the dimension of raw data sets. This demands to truncate the information and omit redundancy and noise. In this work, advanced mathematical algorithms will be investigated, with special attention to non-linear algorithms. The main parameter is robustness of the algorithm. Outcomes of this thesis will be directly applied to data processing in various applications, including the multivariate mapping of sample surface.
Dual-energy computed tomography (DECT) is a modality that was formerly used only at synchrotron-based facilities. Recently it has been used in medical sphere of computed tomography (CT) and nowadays potential of DECT has been tested on lab-based CT system with high resolution. This technique uses two energetically different X-ray spectra for examination and specific differentiation of individual sample components, in terms of materials or tissues, based on their attenuation properties. This differentiation is feasible even for materials which would be inseparable in CT data from standard CT measurement using only one beam energy. Therefore, an advantage of DECT is a possibility of precise material segmentation and classification. Furthermore, acquired information from DECT measurement can be utilized for creating pseudo-monochromatic CT images which results in specific reduction of tomographic artifacts e.g. beam hardening. Aim of this thesis will be study of DECT technique and testing its potential and utilization in sphere of laboratory CT system with submicron spatial resolution.
Despite of evident significance of entropy in various phenomena of materials science, this quantity is neglected in their quantification in majority of cases. This negligence results in inaccurate quantitative values and – in the case of generalization – in incorrect prediction and interpretation of the effects. The aim of this work is to demonstrate the role of the entropy for an important example of solute segregation at grain boundaries of bcc iron. Practical methods of theoretical determination of the entropy of segregation will be developed and the data calculated for selected solutes will be compared to experimental values in literature. The calculated data will be then tested using known phenomena, such as the anisotropy of the grain boundary segregation and enthalpy–entropy compensation effect.
Tutor: Černý Miroslav, prof. Mgr., Ph.D.
The theoretical analysis of novel optical effects and functionalities in modern nanophotonic structures is impossible without adequate and powerful numerical tools. Interestingly, the methods based on eigenmode expansion (EME), enabling a deep physical understanding of the problem, are often overlooked. That is why the project will focus on development and application of EME techniques suitable for the study of selected interesting problems of contemporary nanophotonics. Application will address topics such as nanophotonic lattices that support bound states in the continuum, the issues related with the loss compensation in plasmonic structures, systems with gain and loss where realistic models of gain media based on the rate equations for the populations is used, and modulation in hybrid waveguides with graphene.
Tutor: Petráček Jiří, prof. RNDr., Dr.
Ultra Fast TEM (U-TEM) allows to monitor dynamic phenomena such as phase changes, melting/crystallization of materials with time resolution in ns to ps. Furthermore, samples sensitive to electron beam exposure can be observed using stroboscopic illumination (another U-TEM mode). Current U-TEM microscopes use photoemission sources or a combination of standard sources with very fast deflectors (RF cavity,…). Nanostructured materials appear to be very promising for the production of U-TEM electron sources. For example, GaN materials are seems to be good candidate for this purpose due to their considerable chemical and thermal resistence, low switching voltage of 1.25 V/um and high current density. The properties of the cathode depend to a large extent on the shape and form of nanostructures such as nanotubes, nanocarbons and nanocrystals.
Tutor: Zlámal Jakub, Ing., Ph.D.
The dissertation will deal with the development of electron tweezers, which allows to move droplets of eutectic liquids on the surface of semiconductors. The electron tweezers utilize the focused electron beam and is already tested in the UHV-SEM microscope, developed in cooperation with TESCAN company. During the controlled movement, the gold-containing droplet can for example etch or otherwise modify the surface of semiconductors (germanium, silicon). The dissertation thesis should focus on the interaction of different eutectic droplets with various substrates including 2D materials (graphene, etc.). Part of this work will be optimization of this process including its real-time monitoring using UHV-SEM microscope.
Tutor: Bábor Petr, doc. Ing., Ph.D.
Additive manufacturing offers an effective option of design and rapid prototyping for diverse industry branches. It is expected that these techniques will find applications in small- to medium-scale production in the case of critical components with high production and service demands. Generally, additive manufacturing opens novel and revolutionary production opportunities in terms of shape complexity, previously impossible to achieve by conventional manufacturing processing. One of the most frequently used techniques of additive manufacturing is selective laser melting which utilizes powder feedstock, which is locally melted by the controlled movement of a laser beam. The melting and subsequent solidification results in the fabrication of a structure with the desired shape. Recently, several studies explored the possibility to control the solidification process by laser scanning parameters optimization with the aim to control the crystallographic orientation of microstructure. This approach opens the novel and interesting options for the industry – the fabrication of complex components with tailored microstructure with respect to expected service loading. The topic of PhD thesis will be focused on optimization of selective laser melting parameters to obtain materials with certain microstructure and subsequent characterization of the effect of various crystallographic orientation on fatigue behaviour and fatigue performance. The student will cooperate tightly on SLM processing parameters optimization with the research staff of the NETME centre. Furthermore, the student will adopt deep user knowledge of scanning electron microscopy (SEM) which will be intensively used for the characterization of fabricated microstructures. Fatigue tests will be carried out by modern Instron and MTS testing machines. Obtained results will be analysed with relation to the findings of thorough characterization of deformation mechanisms detected by optic and electron microscopy. The results will contribute to a deeper understanding of fatigue resistance of SLM-processed steels. Objectives of the thesis: 1. Selective laser melting optimization with the aim to obtain structures with strong anisotropy in prominent crystallographic directions. 2. Comprehensive characterization of cyclic stress-strain response. 3. Fatigue performance description of particular structures with respect to a given type of anisotropy. 4. Analysis of active deformation mechanisms and characterization of typical processes related to fatigue damage.
Tutor: Šmíd Miroslav, Ing., Ph.D.
3D printing represents an additive manufacturing method with an unprecedented control over the shape of the printed body and its internal structure. One of the shortcomings of the simple FDM techniques is inability to print cellular solids without the use of a secondary supporting material. Auxetic materials are porous structures characterized by the negative Poisson´s ratio. 3D printing enables fabrication of cellular structures with gradient of porosity as well as gradient of Poisson´s ratio, resulting in metamaterials with unprecedent mechanical properties. Frantal polymerization is a novel polymerization technique enabling low energy in-situ polymerization of various monomers within any cellular structure. The project will investigate auxetic structures printed using light initiated epoxy matrix systems including their complex mechanical and thermomechanical response. It will also involve characterization of the morphology, reaction kinetic assessment with FTIR, photo-DSC, and photo-rheology, mechanical and thermomechanical measurements with DMA.
Aerogels are a unique class of highly porous, solid materials that are characterized by network-like, mesoporous, open-pore microstructure and have a complex of exceptional characteristics, such as extremely high surface area, low density, high catalytic activity, negligible heat conductivity, etc. A promising research area is the surface functionalization of aerogels and other related highly porous architectures (xerogels, ambigels) with catalytically active species. This will allow to use these materials for a wide range of environmental applications, such as catalysts for the treatment of air and water pollutants. The present work aims at the exploration of new possibilities for the development of improved environmental catalysts based on modified single-phase and multicomponent aerogels. Synthesis methods to be used will allow to employ various oxide systems for building aerogel templates (based on perovskite, pyrochlore, zirconia, titania, etc.), while several other techniques (sol-gel synthesis, nanoparticle introduction, etc.) will be applied to modify the obtained templates to prepare catalytic systems, which will be used for air and water pollutant capturing and decomposition.
Tutor: Tkachenko Serhii, Ph.D.
The PhD project will concentrate on a study of complex issues related to development of UV detectors using GaN (Ga)/graphene nanostructures. The initial part of the study will focuses on the preparation of Ga and GaN nanostructures on poly-and single-crystal graphene using a low-temperature deposition method. The low temperature growth of GaN nanocrystals will be carried out by a combination of UHV PVD technologies such as Ga vapour deposition and low energy nitrogen ion-beam (50 eV) post-nitridation using a unique ion-atomic beam source [1] . The growth of GaN will be realized at much lower temperatures (T<250°C) than in conventional technologies (e.g. MOCVD, 1000°C). Subsequently, the relation between parameters/functional properties of Ga and GaN nanostructures and deposition conditions will be studied. The complex characterization of the Ga (GaN)/graphene nanostructures will be provided by Scanning Electron Microscopy (SEM), Scanning Probe Microscopy (AFM, EFM, SKFM), Raman spectroscopy, photoluminescence micro-spectroscopy, etc. Finally, the electrical response of the nanostructures to UV radiation will be studied via a FET-setup utilizing these optimized nanostructures as photosensitive elements. References: [1] J. Mach, P. Procházka, M. Bartošík, D. Nezval, J. Piastek, J. Hulva, V. Švarc, M. Konečný, and T. Šikola, Nanotechnology, Vol. 28, N. 41 (2017).
Spin waves in the THz region have become a subject of growing interest due to a high group velocity of magnons (steep dispersion curve) which renders them attractive for the design of ultrafast spintronic devices [1]. Here, antiferromagnetic materials like rare earth orthoferrites (RFeO3) could be a solution because of their very high (terahertz) frequencies of spin resonances [2], [3]. However, due to the lack of efficient sources and detectors, the physics of magnons at THz frequencies is far less studied. The proposed interdisciplinary PhD study combining photonics and magnetism is based on generation and detection of THz spin waves by near fields enhanced by plasmonic resonant structures - antennas. It brings a new qualitative view into this subject. The antennas will be fabricated on a substrate surface, ideally on ribbons or magnonic crystals made out of RFeO3 thin film samples (e.g. TmFeO3) by EBL/FIB at CEITEC. Then, the magnons propagating along these structures will be analysed by a Brillouin light scattering (BLS) micro-spectrophotometer [4], using the method reported in [5] and successfully implemented at CEITEC [6]. Further, to extend the detected Brillouin-zone range, plasmonic resonant nanostructures providing large momentum components in their near-field hot spots will be used as well [7]. In this PhD study, plasmonic resonant structures for generation and detection of magnons should be optimized, and then dispersion relations tuned by shape, dimensions and periodicity of ribbons/magnonic crystals [6] and external magnetic field. Supportively, magnetic near-field enhanced THz T-D spectroscopy might be applied to test magnon-polariton dispersion curves of the thin film samples according to [3]. References: [44] K. Zakeri, PHYSICA C 549, 164, 2018. [45] J. Guo, J. Phys.: Condens. Matter 32, 185401, 2020. [41] K. Grishunin, ACS Photonics 5, 1375, 2018. [46] T. Sebastian, …, H. Schultheiss, Front. Phys. 3, 35, 2015. [47] K. Vogt, …, B. Hillebrands, Appl. Phys. Lett. 95, 182508, 2009. [38] L. Flajšman, …, M. Urbánek, Phys. Rev. B 101, 014436, 2020. [X] R. Freeman,,…., Phys. Rev. Research 2, 033427 (2020).
Graphene-based variable barrier interface transistors present a promising concept for organic semiconductor devices with several advantages, i.e., high driving current, high-speed operation, flexibility, and scalability while being less demanding for lithography. However, this research requires a multilevel experimental approach, as the substrate determines the growth of the first layers, which, in turn, influences the growth of thin films. The goal of the Ph.D. is to describe and optimize the growth of organic semiconductors on graphene from the mono- to multilayers. The Ph. D. study's experimental research within the Ph.D. study aims to understand the kinetics deposition/self-assembly phenomena of organic molecular semiconductors as a function of temperature, flux, and graphene doping. We will employ a range of complementary techniques including low energy electron microscopy, X-ray and ultraviolet photoelectron spectroscopy and scanning tunneling microscopy, all integrated in a single complex ultrahigh vacuum system. The Studies are supported by a running project. (For detailed information, please, directly contact Jan Čechal)
Control of PVDF phase growth is complex task which depends on parameters of the material preparation. The work is expected to describe hydrogen-bond induced growth of crystalline PVDF phases. The substrates for PVDF crystallization should be systematically processed in order to empirically demonstrate the PVDF crystallization. The experimental data are expected to be supported by quantum chemistry modeling.
Tutor: Sobola Dinara, doc. Mgr., Ph.D.
Hydrogen is a very prospective and eco-friendly fuel which can bring significant economical and environmental benefits. The main obstacle that impedes expected future of hydrogen technology is safe and acceptably efficient hydrogen storage (HS). It is generally accepted that a possible solution to this problem is HS in solid phase of metallic materials (HSM). However, there are not HSMs up to now with sufficient HS properties at low temperature and pressure. Therefore, the main idea of this study is to investigate HS properties of new perspective model alloys which could show effective HS at temperatures near to room temperature and at low pressure. One of ways how to influence HS properties HSM is to change their phase and chemical composition. The results could lead to new strategies in development of HSM.
Tutor: Král Lubomír, Ing., Ph.D.
Hydrogen is a very prospective and eco-friendly fuel which can bring significant economical and environmental benefits. The main obstacle that impedes expected future of hydrogen technology is safe and efficient hydrogen storage (HS). It is generally accepted that a possible solution to this problem is HS in solid phase of metallic materials (HSM). However, there are not HSMs with sufficient HS properties at low temperature and pressure. Therefore, decreasing the thermodynamic stability of hydride phase of HSM with high hydrogen capacity is crucial for tuning their HS properties. One of ways how to influence thermodynamic properties is changing of structure states and chemical composition of HSM. The main idea of this study is to investigate the HS properties of model Mg-alloys in various states of structure from critically cooled or amorphous state to ordered crystallized structure. These materials could show desired HS properties at lower temperatures and pressures. The results could indicate new ways for development of new HSM.
The Low Energy Ion Scattering (LEIS) has proved its capability to study composition of the solid state surfaces. It is a low energy modification of the famous experiment of Rutherford with scattering of alpha particles on gold foil. The extreme surface sensitivity of the technique is widely used in analysis of the elemental composition of a topmost atomic layer with nanometre depth resolution. The sensitivity of the methods originates mainly from charge exchange mechanisms between the projectile and involved surface atoms. Only a small fraction of the scattered projectiles leave the surface in ionized state. This ion fraction is represented by characteristic velocity that is the measure of the charge exchange processes and is characteristic to the given combination of projectile and surface atom. The characteristic velocity is frequently influenced by chemical arrangement of the sample surface as well. This project aims to the characterisation of the charge exchange processes between the He and Ne ions (projectiles) on variety of solid state surface and thin layers. The primary kinetic energies of the projectiles will be varied within the range between 0.5 keV to 7.0 keV. Outputs of the project will significantly improve the potential of the LEIS technique at the field of quantitative analysis. The experiments will be performed on dedicated high sensitivity LEIS instrument – Qtac100 (ION TOF GmbH). See for example: Highly Sensitive Detection of Surface and Intercalated Impurities in Graphene by LEIS. (By S. Prusa and H.H. Brongersma).
Tutor: Průša Stanislav, doc. Ing., Ph.D.
Nanoparticles and nanoparticle systems have a unique position among nanomaterials. They have many important applications in technologies, biology, and medicine, and a huge potential for future developments. The physical and chemical properties of nanoparticles (nanometric volumes of materials) are fundamentally influenced by their morphology. Decreasing the particle size enlarges the surface-to-volume ratio, which can be utilized in chemical reactions (chemical catalysis), and to tune physical properties of these materials (quantum dots, superparamagnetic and magnetic nanoparticles). The topic of this dissertation is the structural and phase characterizations of nanoparticles and their aggregates using electron microscopy. The experimental results will help to unravel the relationship between their properties and structure, and will be used to optimize their synthesis method and functionalization.
Tutor: Pizúrová Naděžda, RNDr., Ph.D.
The work will focus on determining the structure-design-properties relationship of nickel-based superalloys as an ever-progressive material. The topic of the work will be to characterize the influence of casting defects and structural notches representing stress concentrators on the fatigue life of engineering components. In particular, the relationship between the microstructure of the superalloy and its tolerance to defects during cyclic loading at elevated temperatures will be monitored. Fatigue tests will be performed on samples without and with structural notches. While scanning electron microscopy will be used for structural analysis and determination of the effect of structural defects, transmission microscopy will be used for deeper analysis of operating mechanisms of fatigue damage. The results of the work will extend knowledge about the influence of defects on the fatigue life of nickel-based superalloy components and help predict their fatigue life.
Tutor: Fintová Stanislava, doc. Ing., Ph.D.
This thesis will focus on the assessment of the effects of surface treatment by the LSP method on various types of alloys. Laser shock peening (LSP) cures the surface using a pulsed laser beam, which generates a strong compression shock wave upon impact with the surface of the material. The shock wave propagates through the material and creates compressive residual stresses on the surface of the material. This increases the resistance of the material to certain defects or increases the hardness of the surface layer. Various microscopic methods, X-ray diffraction and other methods will be used to characterize the material.
Plasmonic waveguides were demonstrated to be an ideal component of monolithic infrared sensing platforms. While at present, they are commonly used for the confinement and guidance of optical modes, they offer a lot of potential to make a transition from purely passive to functional components of optical systems. The candidate should investigate the fabrication of metal-dielctric stacks for sensing applications at near- and mid-infrared wavelengths by UHV sputtering processes. Experimental work will include the optimization of the deposition processes, as well as lithographic structuring and device characterization. Previous experience with relevant equipment within the CEITEC Nano Facilities (UHV sputtering, lithography, ellipsometry) is of advantage. Applicants should be fluent in English and committed to self-motivated work in an international research group. Further relevant skills include utility programming for data analysis and lab automation (e.g. C++, Ruby, Python, Linux) as well as documentation and publication of results (LaTeX, etc.). The group of Dr. Hermann Detz focuses on novel materials for sensing applications in near- and mid-infrared sensing platforms. Particular emphasis is placed on the integration of novel plasmonic materials with established III-V optoelectronic devices. The group provides a multi-disciplinary, international environment. Scientific results are published in peer-reviewed journals and presented at international conferences.
Tutor: Detz Hermann, Dr.techn. Ing.
There is growing interest in understanding magnetism of materials combined with 2-dimensional materials such as graphene. In particular, the impact of magnetic materials intercalated between the 2D material and its supporting substrate has the potential for magnetic ordering and may lead to modification/control of magnetic properties. Additionally, a system of magnetic material + 2D material could potentially be monolithically integrated with other devices to create new, robust electronic functionalities. The objective of this project it to develop and carry out strategies of intercalating magnetic atoms and molecules using graphene or other 2D materials. The subsequent structures would then be characterized by a wide range of surface probes as well as high field and frequency electron spin spectroscopy and nuclear magnetic resonance techniques. The knowledge gained will then be used to develop predictive models of magnetism for the intercalant + 2D material/substrate. This work will be carried out in collaboration with the US Naval Research Laboratory and will have opportunities for on-site research.
Magnetism emerges in matter due to the presence of unpaired electronic spins and the interaction between them in a wide range of materials from oxides to molecular materials. The collective behavior of spins, also known as quantum entanglement of spins, is a very active area of research with application to communication and computation. Electron spin resonance (ESR) is a key technique that enables to investigate spin states and spin-spin interactions. It has been successfully applied to monomeric and dimeric spin systems for identifying quantum transitions between entangled phases by varying parameters such as the temperature or the orientation of an external applied magnetic field. The aim of this project is to identify suitable materials such as spin dimers of molecular nature and apply ESR spectroscopy to study quantum phase transitions in the high frequency (up to 1 THz) and high field (up to 16 T) regime.
Laser ablation of matter is an essential process involved in the chemical analysis using various techniques of analytical chemistry. The spectroscopic investigation of characteristic plasma emission provides qualitative and quantitative information about the sample of interest. Standard analysis is based on the processing of emission signal; the process of laser ablation and consecutive development of laser-induced plasma is marginal and of little analytical interest. But, understanding the complexity of laser-matter interaction is a crucial step in the improvement of the latter data processing approaches. Thus, this work will target the investigation of spatial and temporal development of laser-induced plasmas, imaging of plasma plumes and determination of their thermodynamic properties. Outcomes of this work will be used in further advancement of the ablation of various materials (incl. biological tissues), improvement of optomechanical instrumentation (collection optics) and optimization of signal standardization.
Plastic recycling and production is currently at its climax, current legislative is forcing faster processing of material while avoiding toxic metal content. Plastic industry is looking for solution in analytical chemistry, with high throughput and satisfactory analytical performance. Laser-induced breakdown spectroscopy (LIBS) technique is being intensively applied in various industrial applications. Its robustness and instrumental simplicity drive its direct implementation into production processes and even to production lines. The goal of this thesis is design of LiBS instrumentation, methodological protocol for classification of individual plastic materials and detection of toxic metals using LIBS spectra.
Laser-Induced Breakdown Spectroscopy (LIBS) method excels for its ease of use and robust instrumentation with stand-off capability reaching high analytical performance. Those benefits are favorable for its implementation to various industrial applications, including civil engineering, as advanced sensors enabling elemental analysis. Here, the detection of ions (e.g., Cl-, Na+, K+) and their impact on the structure properties is of primary interest when estimating the degree of corrosion and other means of material degradation. This thesis aims to establish a methodology for accurate estimation of selected analytes in concrete matrix with their potential in-situ utilization.
Laser-Induced Breakdown Spectroscopy (LIBS) is getting established in various industrial applications. This method excels for its instrumental simplicity and robustness and is thus a potential alternative for existing techniques. When considering LIBS as an analytical tool, it is necessary to evaluate its analytical performance and the level of implementation into the existing production line. The topic of this thesis is the identification of individual industrial applications and the development and adaptation of analytical apparatus together with the optimization of measurement methodology from sample pretreatment to data processing.
The lipid-based delivery system is gaining significant attention from researchers working on the development of novel formulations for improved therapeutic efficacy and safety of drugs. Topical drug delivery is needed in the treatment of skin, eyes, rectum, vagina disorders, and systemic disorders having skin manifestations. Lipid nanocarriers have a widespread application in topical drug delivery due to the biocompatible, biodegradable, nontoxic and nonirritating nature of the lipid. Microemulsion and nanoemulsion contain lipids in the nanosize range which can lead to penetration of the drug to the deeper skin layers. Solid lipid nanoparticles and nano lipid carriers act by forming an occlusive layer on the skin leading to increased hydration and penetration of the drug.
The topic aims at optimizing quantitative analysis of cell behavior with high accuracy for measurements of cell reactions to experimental treatments with applications in cancer research. The topic involves cell culture, specimen preparation for microscopy, time-lapse acquisition, image processing, data analysis, and interpretation. Requirements: knowledge of fundamentals of optics, cell biology, microscopy, coding, the ability to work independently and in a team, and high motivation.
Tutor: Chmelík Radim, prof. RNDr., Ph.D.
The PhD project is aimed at the study of strong coupling between the localized surface plasmons in antennas and phonons in resonantly absorbing non-metallic environments and, consequently, to exploitation of this knowledge for finding and utilizing general principles of spatially localized plasmon-enhanced absorption. The study will tackle this issue in the near IR and mid-IR range and verify it in new types of uncooled antenna-coupled microbolometers with improved sensitivity and spatial resolution response. Due to common characteristics of index of refraction at absorption peaks/bands of materials, the outcomes and conclusions can find direct applications in other spectral regions, regardless the physical origin of resonant absorption. It will make it possible to carry out research on challenging phenomena exploitable not only in the local heating of materials, but also in IR and light detection, energy harvesting, (bio)sensing, quantum technology, etc. References: Břínek L. et al., ACS Photonics 5 (11), 4378-4385, 2018
Single molecular magnets (SMM) are molecular entities bearing nonzero magnetic moment. In addition to the magnetic properties SMM provide one important attribute: they represent two-state system that can be in superposition state, i.e., SMM represent quantum bits (qubits). Recent developments pushed the coherence properties of individual magnets to the range required for competitive qubits. However, for any future application the molecular qubits should be processable as thin films. Moreover, the individual qubits should be mutually interacting. The goal of PhD study is to prepare long-range ordered arrays of molecular qubits on solid surfaces a possible basis for a molecular quantum registry. The experimental research within the PhD study aims at the understanding of deposition/self-assembly phenomena of organic compounds containing magnetic atoms on metallic and graphene surfaces. A special focus will be given to graphene surfaces that provide means to control their electronic properties (by intercalation or external gate voltage) and, hence, mutual interaction of individual spins. The spin coherence properties will be investigated by cooperating partners at CEITEC and University of Stuttgart. (For detailed information, please, directly contact the Jan Čechal)
The goal of the project is developing process for preparing structural foams, in which the wall material is a composite with auxetic inclusions, and which have a prescribed porosity and Poisson´s ratio profile and minimized thermal expansion coefficient.
So-called high-entropy alloys represent one of the most promising classes of modern materials. They are characterized by specific atomic distributions when a number of chemical species randomly occupy crystalline lattice positions. Combination of different elements and their concentrations provide materials with a wide range of unique properties. After years of intensive research focused on mechanical properties of high entropy alloys, the international scientific community has become recently interested in their magnetic properties. These will be the main topic of the proposed PhD program. The planned measurements will be supported by theoretical simulations. The research will be based on a recent cooperation of Czech, German, Austrian and American scientists: O. Schneeweiss, M. Friák, M. Dudová, D. Holec, M. Šob, D. Kriegner, V. Holý, P. Beran, E. P. George, J. Neugebauer, and A. Dlouhý, Magnetic properties of the CrMnFeCoNi high-entropy alloy, Physical Review B 96 (2017) 014437.
Switchable systems based on metal complexes able to change magnetic properties are highly attractive for sensor applications, new electronic devices, or active smart surfaces usable in materials providing high-density data storage. For these applications, the magnetic activity of metal complexes can be utilized and furthermore, it can be modulated by modification of their coordination, redox, electronic and ligand field properties. Three ways to obtain such function are to vary the ligand field strength, switching the coordination chemistry or switching the degree of coupling between two spin metal ions in the case of polynuclear compounds. The aim of the project is to synthesize bi- or multistable metal complexes incorporating switch regulation site in order to perform controlled spin change. Our systems will be characterized by different physical techniques: high field and frequency EPR and NMR spectroscopy, Mass spectrometry, SQUID and X-Ray crystallography.
Multiferroics are perspective materials for microelectronics, spintronics and sensory technology. Multiferroics combines advanced properties of minimum two types of materials as: ferromagnetics, ferroelectrics and ferroelastics. The work will be dedicated to the analysis of the mechanism of the magnetoelectric effect. The dissertation is supposed to include determination of the effect of electrical polarization and mechanical stresses on the magnetic structure.
Localized surface plasmons (LSP) generated in metal nanoparticles (plasmonic antennas) can exhibit various modes differing in energy, charge distribution (dipoles vs. multipoles) and radiation capability (bright and dark modes). One of the most effective methods enabling generation and characterization - mapping of these modes at the single antenna level is Electron Energy Loss Spectroscopy (EELS) provided by High-resolution Scanning Transmission Electron Microscopy (HR STEM). The PhD study will be aimed at application of HR STEM-EELS for mapping the modes of LSP in plasmonic antennas. The emphasis will be especially put at a study of hybridized modes of coupled antenna structures and/or strong coupling effects between modes in plasmonic antennas and excitations in their surrounding environments. These excitations will be polaritons in quantum nanodots localized nearby antennas (the visible range) and/or phonons in absorbing antenna substrate membranes (IR – mid IR). In the former case, the experiment will be carried out by HR STEM-EELS at CEITEC Nano infrastructure (Titan), in the latter case, by Nion Ultra STEM available at some laboratories abroad (e.g. Oak Ridge national laboratory).
The aim of the study is to delimit a region of mechanical stability of selected crystals under nonhydrostatic triaxial loading. For this purpose, phonon spectra will be computed for the crystals in their ground states as well as in deformed states. Phonon spectra will be obtained using force constants that will be computed by the VASP code.
Creep strains measured at very low applied stresses are, by their properties, very different from those measured at higher stresses during the conventional creep tests [1]. The stress and strain dependencies of the creep rate are much weaker and the strain is mostly anelastic. Deformation mechanisms controlling these strains are not known, mainly because there are no observable signatures of the small strains in the microstructure. The small strain kinetics is clearly related to the internal stresses build-up. At present, only one simplified micromechanical model exists which is based on the dislocation segments bowing. This model combines the viscous glide and climb of dislocations [2], but its predictions are only relevant for very small strains, not explaining the transition to the normal plastic creep regime. The main topic of the thesis is the development of the complex dislocation model which will provide better insight into a nature of creep strains which accumulate at very low stresses. The model should also address the transition into the normal plastic creep regime. The solution will be based on the simplified model mentioned above and will include realistic description of the interactions between dislocations and solute atoms. Recently developed discrete dislocation dynamics method [3] will facilitate a statistical description of dislocation segments reaching a critical stress condition. Experimental study of the low-stress creep of the selected metallic materials will be important part of the work. The materials having exceptional creep behaviour observed during the conventional creep tests will be targeted. The Institute of Physics of materials AS CR [http://www.ipm.cz] , which is fully equipped with all the required facilities, will be the workplace .
Tutor: Kloc Luboš, RNDr., CSc.
Metal-insulator transition (MIT) is a phase change between high-conductivity and low-conductivity state of matter, typically related to strong electron-electron correlation. Materials exhibiting MIT are promising candidates for applications in fast optical switching or novel optical elements. While the mechanism of MIT is satisfactorily understood in bulk materials, much less is known about the role of domain boundaries, atomic-scale defects, or interfaces in nanostructures. Ph.D. thesis shall focus on utilizing temperature-dependent analytical electron microscopy to gain a deep insight into the interplay between temperature, local crystal structure, and electronic structure for MIT in a specific material, possibly vanadium dioxide.
Tutor: Křápek Vlastimil, doc. Mgr., Ph.D.
Periodic arrays of ferromagnetically coupled transition metal atoms on topological insulator surfaces are predicted to break time-reversal symmetry. This can result in the emergence of, e.g., a quantum anomalous Hall effect, showing a wide range of interesting physical properties and potential applications, e.g., in spintronics and quantum devices. The goal of Ph.D. is to prepare periodic arrays of magnetic atoms embedded in 2D metalorganic networks (MON) on topological insulator (Bi2Se3, Bi2Te3) substrates. The MONs will be prepared via self-assembly from molecular precursors and transition metal atoms. Their properties will be investigated by a combination of surface-sensitive UHV techniques (low energy electron microscopy and diffraction, scanning tunneling microscopy, and X-ray photoelectron spectroscopy) with frequency domain EPR and magneto-optical spectrometry. The goal is to realize the hybrid organic-inorganic material system, describe the growth kinetics to obtain large area MONs, optimize their structure to display the long-range ferromagnetic order, and tune the Fermi level position by adsorbate doping. The Studies are supported by a running project. (For detailed information, please, directly contact Jan Čechal)
Presence of internal interfaces is important for functional properties of bulk materials as well as for properties of nanoparticles. Interfaces can serve as barriers for dislocation glide or mediate plasticity by themselves. Besides, internal interfaces can affect shape and symmetry of nanoparticles. Twin boundaries are specific kind of interfaces, which have special symmetry and, as rule, low energy. Variety of twin modes are known for materials with non-cubic symmetry (Mg, Ti, Ni-Ti etc.), where twin boundaries can occur as consequence of plastic deformation, crystal growth or phase transformation. However, this process is often spontaneous and development of methods to control the process is important and still unsolved problem. This project is devoted to computer simulations of twinning process in order to develop methods how to reach of initiation and subsequent growth of specific type of twin in non-cubic metallic materials.
Tutor: Ostapovets Andriy, Ph.D., Mgr.
The project deals with developing a microfluidic system for assaying in vitro barrier tissue integrity. It is an important measurement for organ-on-a-chip barrier tissue devices due to its usefulness and non-invasive nature. The work focuses on development and fabrication of multilayered porous membranes with highly ordered pores made of a polymeric material such as parylene. The fabrication processes will be optimized to achieve membranes with different pore geometries. Furthermore, the deposition of electrodes for measuring impedance characteristics will be studied. The membranes integrated into the microfluidic PDMS chip will also serve as a carrier for culturing cell monolayers in which transcellular electrical resistivity will be measured. The proposed design of the membrane and the measurement setup could better monitor cell layer characteristics within any organ-on-chip in vitro.
Candidate will construct microrobots powered by chemicals for environmental remediation using polymer and inorganic chemistry approach.
Tutor: Pumera Martin, prof. RNDr., Ph.D.
Geometric-phase optical elements are a new tool for complex light shaping and generation of special states of light. Unlike traditional refractive elements, the geometric-phase elements control the light using transformation of its polarization state. Thanks to technology of liquid crystals or principles of plasmonics, geometric-phase elements provide abrupt phase changes on physically thin substrates. Compact size and unique polarization properties make them ideal candidates for simply integrable spatial light modulators. The dissertation thesis topic is to find and verify the potential of geometric-phase elements in common-path digital holography and advanced optical microscopy.
The aim of this Ph.D. topic is to investigate green and facile synthesis of CDs using microwave-assisted hydrothermal method or plasma synthesis from small organic molecules. Carbon dots (CDs) are a fascinating class of fluorescent nanomaterials, usually defined as carbon nanoparticles with a diameter below 10 nm. This family of materials includes graphene quantum dots (GQDs), carbon quantum dots (CQDs), carbon nanodots (CNDs), and carbonized polymer dots (CPDs). CDs display fluorescence depending on the excitation wavelength, excellent chemical stability and photostability, high water solubility, good biocompatibility, and low toxicity. Furthermore, they can be easily functionalized with other molecules (proteins, drugs, fluorescent dyes, etc.). By controlling the structure and size, their properties can be tailored to satisfy the demands of diverse applications in biomedicine, optoelectronics, solar cells, fluorescence sensors, photocatalysis, electrochemistry, and lithium-ion batteries. The thesis will study how the structure and dopping of CDs influence their functional properties, namely fluorescence and biocompatibility.
Auxetic materials are materials with a negative Poisson's ratio. Their specific feature is that, unlike standard materials, they expand in the perpendicular direction during tensile deformation. This factor gives a wide range of applications for highly stressed components, which should be fixed. Auxetic material cannot be easily removed from the place where it is fixed. Their disadvantage is low rigidity. One way for auxetic material reinforcement was when combined with a conventional porous material with a positive Poisson's ratio. The student will deal with various possibilities of combining materials with negative and positive Poisson's ratio. The effect of reinforcement and stress distribution during deformation will be investigated. Materials will be theoretically described using solid-phase mechanics.
For detailed info please contact the supervisor.
Tutor: Kalousek Radek, doc. Ing., Ph.D.
The aim of the work will be to describe the molecular motion of water in macromolecular systems by molecular dynamic simulations. Water in macromolecular systems usually moves in a random Brownian motion. Nevertheless, there exist materials, where motion of water molecules is directed. One molecular system with directed motion will be investigated. The student will investigate this system by the molecular dynamic simulations, and he/she will describe the mechanism of the directed motion. The student can design his/her model or choose one of the models that are currently investigated. The first example is a hydrogel in which motion is controlled by water groups fixed in space. It has been found that the combination of interacting groups with fixation in space causes better adsorption of water compared to the groups with motion. The aim of this study will be to discover the mechanism of increased adhesion. The second example is a phenomenon called durotaxis, where a drop of water moves on the surface of the material in the direction of stiffness gradient. Durotaxis on rigid surfaces is currently well described. The mechanism of durotaxis on soft surfaces is currently partly described. However, there is still a good area to describe all aspects of such a motion. The topic is investigated in cooperation with the Institute of Physics of the Polish Academy of Sciences in Warsaw.
Multiferroics are perspective materials for microelectronics, spintronics and sensor technology. Multiferroics combines advanced properties of minimum two types of materials as: ferromagnetics, ferroelectrics and ferroelastics. Using these materials’ properties can also contribute to design of smart photovoltaic structures. The work will be dedicated to the analysis of the contribution of the polarization-driven carrier separation to enhancement of solar cells efficiency.
3D printing represents an additive manufacturing method with an unprecedented control over the shape of the printed body. However, various parts of a single object may require different material properties, such as functional, mechanical, thermomechanical, colour, etc. Multimaterial print is an elegant solution to this issue which utilizes more materials upon the printing of a single body. Nevertheless, the photopolymerization 3D printers could not simply use the multiple nozzle setup with different materials or exchanging the material within a single nozzle. Therefor, strategies of multimaterial photopolymerization 3D printing will be investigated together with the accompanying phenomena such has interlayer adhesion, mutual interference of materials upon post-curing, printing with two parallel initiating systems, advanced post-processing methods, complex mechanical and thermomechanical response of multimaterial structures, or printing of cellular materials. It will also involve characterization of the optical properties of the individual components with UV-VIS spectroscopy, microscopic observation of the printouts’ morphology, reaction kinetic assessment with FTIR, photo-DSC, and photo-rheology, mechanical and thermomechanical measurements with DMA.
Tutor: Lepcio Petr, Ing., Ph.D.
The so-called Rydberg blockade enables the formation of fundamental quantum gates, using ultra cold Rydberg atoms trapped on integrated devices called “atom chips”, a great platform to realize applications for quantum computation as well as simulation. To manipulate these gates and perform the correct operations multiple well defined light fields of different frequencies (ranging from the microwave to the Terahertz regime) are necessary, with obvious advantages of these fields being created within the atom chip itself. Therefore this thesis aims for the realization of such a versatile quantum technology platform, using different technological approaches, such as commercial CMOS technology as well as conventional III-V semiconductors techniques. Previous experience with measurement setups at CEITEC (Lithography, RIE, PE-CVD, SEM, ellipsometry) is of advantage. Applicants should be fluent in English and committed to self-motivated work in an international research group and be willing to travel to international collaborators. Further relevant skills include utility programming for data analysis and lab automation (e.g. C++, Ruby, Python, Linux) as well as documentation and publication of results (LaTeX, etc.).
Prismatic dislocation loops in metals are created by radiation damage or by severe plastic deformation. These loops are then obstacles for dislocations needed for plastic deformation and the material becomes brittle. The prismatic dislocation loops will be studied by molecular dynamic modeling and also by experiments using transmission electron microscopy.
Tutor: Fikar Jan, Mgr., Ph.D.
The aim of the work will be the research of the pore architecture of CaP/SiO2 ceramics and glass-ceramics depending on the preparation method used, preparation conditions and chemical composition and structure of the precursors used. Knowledge about the architecture and structure of pores will be correlated with the mechanical, physicochemical and biological properties of CaP / SiO2 materials and used in bone tissue engineering.
Tutor: Částková Klára, doc. Ing., Ph.D.
The candidate will develop novel nanorobotic systems for cancer drug delivery. The following skills will be learned: nanorobots fabrication, propulsion systems, SEM, XPS, microscopic characterization. Work with biological systems.
The candidate will develop new nanorobotic systems to detect DNA mutations in organisms. He/she will master the following skills: nanorobot fabrication, propulsion systems, SEM, XPS, microscopic characterization. Work with biological systems.
The candidate will develop novel nanorobotic systems for the removal of biofilms from titanium implants. The following skills will be learned: nanorobots fabrication, propulsion systems, SEM, XPS, microscopic characterization. Work with biological systems.
The candidate will develop new nanorobotic systems for microplastics removal and degradation. He/she will master the following skills: nanorobot fabrication, propulsion systems, SEM, XPS, microscopic characterization. Working with biological systems.
The candidate will develop new nanorobotic systems for operation in space in microgravity. He/she will master the following skills: nanorobot fabrication, propulsion systems, SEM, XPS, microscopic characterization. Working with biological systems. Close collaboration with the European Space Agency.
The doctoral thesis is focused on research and development of complex multilayer coating heating systems composed from insulating and electrical resistance materials and produced by means of thermal spray technologies. The changes in physical and materials properties of heating systems will be also studied in detail. The aim of this work is to design of multilayer heating coating system with focus on its manufacturing utilizing powder metallurgy and thermal spray technologies processes, including the study of physical properties of each layer, its structural stability and phase transformations, which can take place within long term isothermal or cyclic thermal exposure. Conventional methods used in the field of material and physical engineering, which are available, will be used to study and evaluate in the frame of this work produced heating systems.
Tutor: Čelko Ladislav, doc. Ing., Ph.D.
A key obstacle in the development of complex multiscale theories lies in our current inability to directly control the structure formation at multiple hierarchically arranged length scales. Directed self-assembly of surface decorated precisely defined NPs represents means for obtaining precisely controlled spatial arrangements of NPs. No theoretical framework has been published describing the laws governing multi length scale assembly of NPs into hierarchical superstructures in polymer continua. We aim at developing experimental and theoretical foundations for novel multiscale hierarchical predictive model of relationships between structural variables, nature and kinetics of the structural hierarchy formation via self-assembly of NSBBs and the physico-chemical and mechanical properties and functions in polymer nanocomposites.
Due to their dimensions comparable with the wavelength of light, nanostructures can directly modify properties of reflected and/or transmitted electromagnetic waves. The discipline investigating the interaction of an electromagnetic wave and nanostructures is called Nanophotonics. Its applications can be found for instance in photovoltaics or enhanced optical spectroscopy. Besides the shape and dimensions of nanostructures, the light can be also modified by their material properties. Recently, many scientific teams have been concentrating on the optically active advanced materials such as perovskites or 2D transition metal dichalcogenides (TMDs). These advanced materials can be often characterized by their photoluminescence, especially using confocal optical spectroscopy, time-resolved spectroscopy, or scanning near-field optical microscopy. All these experimental techniques together with adequate numerical simulations (e.g., FDTD, DFT, BEM) are available at the Institute of Physical Engineering BUT and will constitute the main tools for successful completion of the PhD research project.
The curved-space physics is an exciting research field. Although many phenomena arising from the curvature of space-time had been already observed, some of the curved-space phenomena remain unobserved, e.g. Hawking radiation. The difficulty of observing the curved-space phenomena motivated a novel research method: simulations of curved spaces in a lab. Namely, optical simulations already provided promising results. In the project, student will investigate the capabilities of optical simulation of curved-space physics, with a special emphasis on the imaging properties. To meet this objective, student will employ calculus, differential geometry and numerical simulations. Student will be provided a collaboration with world-leading experts from the University of Glasgow and the University of Exeter.
Tutor: Bělín Jakub, Mgr., Ph.D.
Magnetic materials constitute a highly tunable platform for the design of adaptive optical and magnonic elements. Moreover, coupled order parameters in complex magnetic phase-transition materials can be controlled using various driving forces such as temperature, magnetic and electric field, strain, spin-polarized currents and optical pulses. The Ph.D. candidate will explore the first-order metamagnetic phase transition in materials that have been subjected to strong spatial confinement and optical stimuli and design new functional systems by combining individual structures with well controlled properties into 2D and 3D arrays.
The work will focus on the preparation and direct extrusion 3D printing of composite pastes, which will be enriched with bioactive substances that accelerate healing and ensure the prevention of pathogens in bone tissue engineering. The influence of the composition of the composite paste and additives on the rheological, mechanical and biological properties of the final 3D printed samples will be monitored. The influence of the internal arrangement of printed media and the external environment on the final properties of 3D samples will be evaluated.
Bound states in the continuum (BICs) represent a theoretically interesting way of field localization, which contradicts the conventional wisdom of bound states with energies solely outside the continuum of free states. BICs offer a number of interesting applications; for example, in photonics, BICs enable development of sensitive nanostructures with significant reduction of radiation leakage [1,2]. The project will focus on theoretical analysis and physical understanding of the operation of photonic waveguide structures supporting the propagation of a selected type of BIC. We assume the design and subsequent systematic research of selected photonic waveguide structures that resemble a lattice investigated in Ref. 3 and support the so-called symmetry protected BIC. The student will perform simulations with the aim to confirm the existence of the assumed BICs. Subsequently, the behavior of BICs will be investigated, and structural parameters will be optimized in order to achieve the required properties. [1] K. Koshelev, A. Bogdanov, and Y. Kivshar, “Engineering with Bound States in the Continuum,” Opt. Photonics News, vol. 31, no. 1, p. 38, 2020 [2] S. I. Azzam and A. V. Kildishev, “Photonic Bound States in the Continuum: From Basics to Applications,” Adv. Opt. Mater., vol. 9, no. 1, pp. 16–24, 2021 [3] Y. Plotnik et al., “Experimental observation of optical bound states in the continuum,” Phys. Rev. Lett., vol. 107, no. 18, pp. 28–31, 2011
The proposed Ph.D. project aims to study the plasma processing of nanofibrous mats. The envisaged applications of the mats include health care textile, filtration, protective clothing, and catalysis. The most notable benefit of nanofibrous polymer mats is their porosity and high surface-area-to-volume ratio enabling moisture absorption, promoting the exchange of gases, and providing a high drug loading amount per unit mass. Morphological proximity to the extracellular matrix (ECM) is advantageous for wound dressing and tissue engineering when serving for cell adhesion, growth, and proliferation. Plasma polymerization solves the problem of hydrophobicity or chemical inertness of nanofibers. This project investigates plasma polymerization concerning plasma and surface processes leading to the retention of reactive functional groups, nanoparticle formation, and understanding the penetration depth into microporous materials. Magnetron sputter-deposition of Cu-based coatings onto polymer nanofibers will be studied to prepare antibacterial coatings. The proposed Ph.D. topic is part of two international research projects integrating the collaboration with the Russian Academy of Sciences and Luxemburg Institute of Science and Technology.
In this study plasmonic resonant nano-and micro-structures (particles, antennas, tips) will be used for enhancement of photoluminescence of nanostructures such as nanodots, nanowires and 2D materials (e.g. metal dichalcogenides: MoS2, WS2,....). In this way single photon sources provided by defects of these structures might be recognized.
Progressive sintering techniques enables the fast sintering of advanced ceramic materials, or the development of the final products with unique properties. The typical progressive sintering techniques are: Rapid Sintering, Spark Plasma Sintering, Flash Sintering and the newest Cold Sintering. The task of the proposed topic is the experimental verification of these novel techniques, study the kinetics of the sintering process and finding out the impact of these sintering techniques on the final properties (mechanical, optical, electrical etc.).
This doctoral topic will study the properties of calcium phosphate cements prepared with unconventional liquids. The aim is to understand the rheological properties, the cyclic compression behaviour and the water weakening mechanisms. The research involves the synthesis and preparation of the cement, study the rheological properties, characterize the structure and the mechanical performance, and explore neural networks to predict the mechanical response. Along the studies, the candidate will have the opportunity to learn and work from the synthesis to the characterization of the materials. Highly motivated and collaborative candidates with outstanding track of records and with the ambition to learn from both materials and biological sciences are welcome to submit an application.
Automated real-time analysis of the structure and morphology of high-performance polymeric materials and composites is of utmost importance in order to enable their fast development and production. The objective of the PhD project is to explore the possibilities of X-ray computed tomography (CT) scanning for the quantification and digitization of composite material structures. You will test the limits of standard CT imaging setup for the future usage of in-line systems and use simulations to explore alternative and sparse data acquisition to speed up the imaging process. These simulations will then be used to create a detailed model to establish the experimental parameters and the CT reconstruction procedure.
The possibility to tune the graphene transport properties, i.e., type and concentration of charge carriers, makes graphene an attractive candidate for electronic devices, sensors, and detectors. In this context, various approaches for providing graphene with controlled doping were developed. The original approach – application of an external electric field provided by the voltage between the graphene and a gate electrode – was followed by deposition of atoms or molecules featuring charge donors or acceptors in direct contact graphene. Remote graphene doping based on charge trapping in gate dielectric by visible-, UV-, and X-ray radiation was only recently established. In parallel, the effect of electron beam (e-beam) irradiation on graphene devices was evaluated, and the e-beam also entered the group of techniques capable of providing graphene with remote doping. The goal of Ph.D. is to reveal the mechanism of electron-beam-induced graphene doping, assess the role of defects in the dielectric layer, and develop a theoretical model describing the kinetics of the process. Our current understanding suggests that the key mechanism here is the charging of defects in an oxide dielectric layer, and a p-/n- doping is achieved depending on the possibility of forming electron-hole pairs in the dielectric layer by electron irradiation. We envision the utilization of the project outputs in adaptive electronics and the fabrication of graphene devices, in general. (For detailed information, please, directly contact Jan Čechal)
The topic is focused on development of numerical methods for rigorous simulation of electromagnetic wave propagation in arbitrary inhomogeneous media. Namely, we assume investigation of the techniques based on the expansion into plane waves and/or eigenmodes in combination with perturbation techniques. Developed techniques will applied to modeling of light scattering by selected biological samples. Requirements: - knowledge in fields of electrodynamics and optics corresponding to undergraduate courses - basic ability to write computer code, preferably in Matlab.
Scanning Probe Microscopy techniques (SPM) and particularly Atomic Force Microscopy (AFM) are most common techniques for surface topography measurements. They have however still some limitations, for example its limited scanning range and lack of techniques for sub-surface mapping. Even if the interaction between probe and sample is already including information from sample volume, typically only surface topography or surface related physical properties are evaluated and the sub-surface information is lost. In most of the scanning regimes the amount of recorded and stored data is even so small that the information about sample volume is lost. On the other hand, there is lack of reliable subsurface mapping techniques with high resolution suitable for the growing field of nanotechnology, and methods of SPM tomography have large potential – and we can already see some first attempts for sub-surface mapping in the scientific literature. Aim of the proposed work is to develop techniques for mapping volume sample composition using SPM, particularly based on AC Scanning Thermal Microscopy and conductive Atomic Force Microscopy. This includes development of special reference samples, methodology and software development for control of a special, large area, SPM. In cooperation with the research group also a numerical modeling of probe-sample interaction will be performed and methods for sub-surface reconstruction will be tested.
Tutor: Klapetek Petr, Mgr., Ph.D.
Recent studies have shown that the interaction of a fast electron with an optical field results in modification of the electron’s wavefunction. We could exploit this process in electron microscopes where the injection of tailored light would help shape electron beams on demand. The novel shaped electron probes offer applications such as compressed, fast and aberration-free imaging or selective sample excitation. The PhD thesis will focus on the design of light fields and experimental setups suitable for the generation of tailored electron beams as well as on the development of applications in imaging and spectroscopy.
Tutor: Konečná Andrea, doc. Ing., Ph.D.
Control over thin molecular films composed of single-molecule magnets or quantum bits is crucial in the development of novel electronic and magnetic devices. Their behaviour on surfaces is yet largely unexplored area. This PhD project will use the already existing high-vacuum chamber for thermal sublimation of thin films of coordination transition metal and lanthanide complexes. The student will work on the whole route from a bulk as-synthesised powder to a nanostructured thin film. The final goal is to be able to predict and evaluate the magnetic properties of such films by newly built high-frequency electron spin resonance spectrometer (HF-ESR). Additional surface-sensitive spectroscopic and microscopic methods such as X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and scanning electron microscopy (SEM) will be used to study prepared thin films. The student will communicate and perform tasks in international collaboration with research groups in the USA and Italy.
The work aims at deeper understanding of stability of plasma-sprayed thermal barrier coatings (TBCs) as affected by the roughness of MCrAlY bond coat. Damage mechanisms and damage evolution in TBCs will be examined to identify the optimal topography of the bond coat in order to improve coating performance for components used in propulsion and power generation industries. Conventional MCrAlY + ZrO2-Y2O3 TBCs with the bond coat prepared by plasma spraying using feedstock powders with different size-distribution will be studied under high-temperature isothermal oxidation, thermal cycling, and room temperature mechanical loading.
Tutor: Slámečka Karel, Ing., Ph.D.
Bandstructure engineering of semiconductor heterostructures enables optoelectronic devices with designed characteristics. The material parameters of conventional III-V semiconductors limit the wavelength range of such devices to infrared wavelengths. The scope of this thesis is to characterize and optimize oxide-heterostructures to apply established concepts like electro-optic modulation, non-linear wave-mixing or intersubband detection to shorter wavelengths in the visible or near-UV. Previous experience with measurement setups at CEITEC (SEM, TEM, AFM, XPS, ellipsometry) is of advantage. Applicants should be fluent in English and committed to self-motivated work in an international research group. Further relevant skills include utility programming for data analysis and lab automation (e.g. C++, Ruby, Python, Linux) as well as documentation and publication of results (LaTeX, etc.). The group of Dr. Hermann Detz focuses on novel materials for sensing applications in near- and mid-infrared sensing platforms. Particular emphasis is placed on the integration of novel plasmonic materials with established III-V optoelectronic devices. The group provides a multi-disciplinary, international environment. Scientific results are published in peer-reviewed journals and presented at international conferences.
While additive manufacturing of polymers, has become increasingly popular for design studies, rapid prototyping and the production of noncritical spare parts, its application in structurally loaded components is still scarce. One of the reasons for this might be skepticism of engineers due to the lack of knowledge regarding the expected lifetime and reliability as well as knowledge to failure mechanisms. Therefore presented work will be focused on fatigue damage of additively manufactured polymer materials, experimental testing of such materials as well as on numerical modeling of fatigue damage and fatigue crack propagation. This work will be solved in close cooperation with PCCL- Polymer Competence Center in Leoben.
Tutor: Hutař Pavel, prof. Ing., Ph.D.
Our thorough understanding of magnetic properties is intricately inter-linked with a detailed information about the structure of studied materials. The decreasing particle size and/or temperature resulted in the past few years to the observation of new magnetic states, for example, the superparamagnetism. Importantly, the magnetic states sensitively depend on the atomic structure, crystal boundaries and/or magnetic domains which all significantly change with the temperature. The proposed PhD study will therefore focus on these structure-property relations at low temperatures. The following aspects will be covered: - Preparation of samples by various methods - Structural study of materials by XRD, SEM, TEM, AFM etc. - Magnetic measurements by VSM, PPMS and SQUID
The doctoral thesis will deal with research in the field of catalytic reactions using analytical methods capable of monitoring reactions in real-time. The reactions will be studied by various analytical methods such as UHV-SEM, E-SEM, MS, SIMS etc. aiming to better understand the mechanism of catalytic reactions on different types of surfaces (crystals, nanoparticles) and in a wide range of reaction pressures. In the first phase, the oxidation of carbon monoxide and subsequently other oxidation or reduction reactions important in technical practice will be studied. The work will also include the development of new methods and devices enabling real-time observation under various experimental conditions.
Holographic Incoherent-light-source Quantitative Phase Imaging (HiQPI), developed at CEITEC BUT, is a unique imaging technique providing high-contrast quantitative observation of live cells in tissue culture without labeling. Recent preliminary experiments and simulations have revealed the possibility of reaching sub-diffraction limited resolution (super-resolution) in HiQPI (Ďuriš et al 2022, APL Phot 7, 046105). The approach utilizes the coherence gate effect induced by a low-coherence light allowing us to measure even the complete mutual coherence function in the detection plane, which is unique in digital holography. The design of the microscope permits the use of an arbitrarily low-coherent source. Several approaches to super-resolution and their applicability in HiQPI will be investigated within the dissertation work, including theoretical analysis of each method, proposal of their implementation in HiQPI, and last but not least, the experimental verification using a Q-Phase microscope. The most successful super-resolution approach will then be employed in an experiment with live cells.
Currently there is a big expansion in the development of nanomaterials that find their use in industry. As they become mass spread the risk of leaking into the environment increases and therefore it is necessary to monitor their influence on various ecosystems. Laser-Induced Breakdown Spectroscopy (LIBS) is an optical emission method suitable for elemental mapping of large sample surfaces. The information about biodistribution and bioaccumulation of material in the organism is crucial for correct evaluation of its toxic effect. The LIBS method can detect contaminants in plants with sufficient resolution. The goal of this work is to determine bioaccumulation and translocation of selected nanomaterials in plants.
Novel applications of Nuclear Magnetic Resonance (NMR) spectroscopy and imaging technique to complicated biological macromolecules and organisms create demand for increased sensitivity and resolution of NMR measurements. Dynamic Nuclear Polarisation (DNP) is a unique method to transfer large electron spin polarization in a sample to the nuclear spin sub-ensemble to enhance NMR signal. However, employment of DNP methodology at high magnetic fields (> 5 T), which are typical for modern NMR spectrometers, is not well understood and optimized. In this PhD project the processes of electron to nuclear spin polarization transfer under the action of high frequency microwave irradiation will be studied theoretically. The PhD student will use the already developed theoretical concepts and computational tools to perform quantitative analysis of electron and nuclear spin dynamics responsible for DNP. Further, the student will adapt and elaborate the existing theoretical methods to ensure a good description of experimental results for DNP at high magnetic fields. Generally, the work in this project will be governed by the overall goal which is the optimization of DNP in liquid solution at physiological temperatures based on experimental data collected in CW, rapid scan, pulsed ESR and NMR experiments. The student will participate in international collaborations and scientific meetings to discuss and present the project results.
Tin was historically often used and is still employed nowadays, e.g., in soldering. Interestingly, some aspects of the beta-Sn to alpha-Sn phase transformation (known as tin pest), that turns bulk Sn into a powder, are still not fully understood. Published transformation-related data are, unfortunately, contradictory regarding (1) the mechanism of transformation, (2) the influence of solutes as well as (3) details of the so-called inoculation (insertion of the alpha-Sn into supercooled beta-Sn). The aim of the proposed PhD study is to perform theoretical calculations that will shed a new light on the above mentioned three problems. The calculations will be interlinked with experiments within the Czech Science Foundation project No. 22-05801S in period 2022-2024.
The project will include the study of the optimal conditions for the appearance of magnetoelectric, magnetoresistive and thermoelectric effects. A correlation between the magnetic, electrical, and elastic properties of magnetoelectric materials should be established. A practical application of the results refers to the possibility of information conversion from the form of magnetization into electrical voltage and vice versa. The work relates to the field of energy harvesting and miniaturization of fundamental elements in nanoelectronics.
Theme is focused on the preparation of composite materials filled by expanded graphite with controlled structure providing specific electrical and rheological properties. The relationship between preparation conditions and structural parameters and functional properties will be determined by appropriate characterization methods. The morphology of prepared composite materials and the influence of expanded graphite on the melt behaviour (especially on percolation) will be evaluated. Preparation of co-continuous polymeric blend of thermoplastic will be experimentally studied, for example ethylene and its copolymers-based polymer matrices modified by electro-conductive filler. Satisfactory composite materials can be applied in electrotechnology for jacketing and in means of transport.
The topic of the dissertation thesis focuses on research into flexible self-supporting ceramic foils with a thickness ranging from 0.05 to 1 mm. The research will be concern with the preparation of ceramic foils and with mechanical, electrical, or optical properties of such foils. The basic task will be the development of unique methods for the preparation of ceramic foils from nanoparticulate suspensions. The research will be aimed at electrotechnical applications that utilize ceramic foils as flexible dielectric substrates or piezoceramic energy harvesters.
Tutor: Trunec Martin, prof. Ing., Dr.
Holographic Incoherent-light-source Quantitative Phase Imaging (HiQPI), developed at CEITEC BUT, is a unique imaging technique providing high-contrast quantitative observation of live cells in tissue culture without labeling even if those are immersed in a highly scattering medium (Ďuriš and Chmelík 2022, Opt Lett 46, 4486). Experiments and simulations have shown that the three-dimensional refractive-index distribution of the observed object can be reconstructed from a set (z-stack) of HiQPI images. The approach utilizes the coherence gate effect induced by a low-coherence light allowing us to measure even the complete mutual coherence function in the detection plane, which is unique in digital holography. Further theoretical analysis and optimization of the detection and reconstruction schemes will be necessary to gain high resolution, accuracy, and speed of a computer 3D refractive-index reconstruction. The work will also include experimental verification with a Q-Phase microscope with both model objects and living cells.
Dynamic Nuclear Polarization (DNP) is a phenomenon, that can enhance greatly the NMR sensitivity (several hundred times at least). There are several mechanisms of DNP, though all of them result from the transferring of electron spin polarization (from special polarizing agents) to nucleus. This process is strongly dependent on the electron spin relaxation of the polarizing agent. However, due to the instrument limitations, the spin dynamics of polarizing agents is studied very poorly at frequencies above 100 GHz, especially at frequencies of 263, 329 and 394 GHz, which correspond to NMR proton frequencies of 400, 500 and 600 MHz, respectively. Usually, the spin relaxation properties are studied using the pulsed method. Unfortunately, the nowadays level of microwave sources at THz frequencies, mostly in terms of output power, does not allow the implementation of the pulsed technique in the wide frequency range. For this reason, the Rapid Scan Electron Spin Resonance (RS-EPR) spectroscopy is the only possible technique for the investigation of spin dynamics at THz frequencies. In this project, PhD student will (i) develop and implement a technique of fast frequency sweeps into the high field/high frequency EPR spectrometer (ii) investigate the spin relaxation processes in different DNP polarizing agents in the wide frequency and temperature ranges.
Topological insulators (TIs), which demonstrate conductor properties at surfaces and behave as insulator in the bulk, present unique quantum state properties. Therefore, we have witnessed enormous research interest on these materials. It is anticipated that TI materials have a great potential to serve as a platform for spintronics due to their spin-locked electronic states, which could open new avenues for spintronic, quantum computing and magnetoelectric device applications. Moreover, interfacing TIs with superconducting layers is predicted to create mysterious physical phenomena, ranging from induced magnetic monopoles to Majorana fermions. The present PhD study aims at i) synthesizing theoretically studied topological insulators and ii) investigating topological superconductors, formed by hybridizing TIs and superconductor materials. TI and superconductor thin films will be fabricated via employing physical vapor deposition processes such as magnetron sputtering, pulsed laser deposition and molecular beam epitaxy. The obtained films will be characterized by X-ray diffraction method, X-ray Photo-electron Spectroscopy (XPS), Scanning Electron Microscopy (SEM), and HR (S)TEM and so on. Furthermore, the magnetic properties of the thin films will be examined by Vibrating Sample Magnetometer (VSM). In addition, magneto-transport measurements of these films will be carried out as well.
Plasma polymers deposited in cyclopropylamine/argon radio frequency discharge at low pressure proved to be an excellent platform for immobilizing biomolecules and improving cell adhesion and proliferation [E. Makhneva et al. Sens. Actuator B-Chem. 276 (2018) 447,A. Manakhov et al. Materials & Design 132 (2017) 257, A. Manakhov et al. Plasma Process. Polym. 14 (2017) e1600123]. Similarly, plasma polymers containing carboxyl or anhydride groups are perfectly suitable for biomedical applications, as, e.g., the immobilization of drugs and platelet-rich blood plasma were recently reported [E. Permyakova et al. Materials & Design 153 (2018) 60, A. Soloviev et al. Polymers 9(12) (2017) 736]. Plasma polymer thin films are significantly influenced by external parameters such as gas feed composition, pressure, and power to the discharge. Unfortunately, a detailed understanding of plasma polymerization is difficult because it is a complex chemical vapor deposition process that involves many neutral reactants created in the plasma. Moreover, at low pressure, it is affected by positive or negative ions. This thesis aims to understand the plasma-chemical gas phase and surface processes by using plasma diagnostics methods (optical emission spectroscopy, mass and ion spectroscopies, retarding field energy analysis, and Octiv VI Probe measurements). The information gained will be correlated with the characterization of the thin films.
Noninvasive electrical stimulation of the nervous system is an important goal in bioelectronic medicine. Electrically stimulation at present is limited to shallow targets because of the high electrical impedance of skin and bone, therefore it is difficult to compete with surgically-implantable devices. This project comprises exploring a relatively new method to use high-frequency electric fields which can penetrate tissues with low loss, relying on low-frequency interference patterns to allow stimulation of deep targets. The project will involve developing new interference stimulation hardware as well as computational methods to calculate stimulation targeting. Collaboration with neuroscientists and participation in animal studies is envisioned as an important aspect of the project, as well as support to clinical trials.
The development of ceramic processing has made it possible to prepare polycrystalline ceramics with optical properties comparable to traditional materials such as single crystals or glass. In addition, polycrystalline ceramics offer many advantages, especially in shaping and spatial control of the distribution of active ions. The aim of this Ph.D. study will be the preparation of fine-grained ceramics with a gradient structure of dopants that will provide optimal optical and other required properties for selected applications (laser media, other luminescent applications, optoelectronics, dental ceramics, …). Advanced forming and sintering technologies based on colloidal processing and pressure-assisted sintering will be used to prepare ceramics. Ceramics will be evaluated in terms of efficiency and usability in the intended applications.
The thesis will focus on finding efficient routes to control magnetic configurations without applied magnetic fields using femtosecond laser stimuli. The physical phenomena involved are linked to ultrafast spin dynamics and the associated energy and angular momentum transfer between the spins, electrons, and lattice. The proposed experimental approach will exploit magnetic heterostructures to generate collective magnetic excitations. The project assumes previous experience with optical set-ups.
The main objective of the proposed project is to investigate effects of structural variables such as molecular weight, supermolecular structure and interfacial adhesion on the fracture behavior of composites with polymer matrix based on recycled PE/PP compatibilized with suitable means. Principál goal of the project is the quantification of the structure – property relationships with emphasis on the molecular and supermlecular structure of the recycled PE/PP blends, interactions between PE/PP matrix and the reinforcing short fibers or graphenoids and the fracture mechanisms under both static and dynamic loading conditions. The results of the proposed project will enable to optimise the material’s composition with respect to the selected applications and will allow to expand application range of these materials into structural applications with greater added value.
Laser-Induced Breakdown Spectroscopy (LIBS) finds its benefits in the analysis of biological tissues and becomes an interesting alternative in medical applications. The main advantage of LIBS in said applications is the detection of macro- and microbiogenic elements and the change of their relative abundance in the investigated sample area, e.g., cross-section of malignant and healthy tissue. The primary interest is in the laser ablation of selected soft tissues, organs of model organisms (namely laboratory mice) and clinical human samples (e.g., skin biopsy). Thus, the goals of the thesis aim the whole-slide imaging of samples with high lateral resolution and advanced interpretation of obtained elemental images. The latter is the most crucial for further improvement of LIBS within the scope of biological and medical applications while providing biologically relevant information. Finally, LIBS results will be complemented with the use of standard optical microscopy (histopathology) and other analytical techniques, namely laser ablation inductively coupled plasma mass spectrometry, to provide a platform for correlative imaging.
The study will be aimed at design, fabrication, and characterization of resonant plasmonic nano- and micro-structures (“diabolo” antennas, split ring resonators, etc.) providing a significant local enhancement of magnetic components of electromagnetic fields. The structures with resonant properties particularly in the IR and THz will be studied, with respect to their potential applications in relevant spectroscopic methods.
The doctoral thesis will focus on research and development of new analytical approaches in the field of secondary ion mass spectrometry (SIMS) and electron microscopy for the study of nanostructures and their ability to moderate catalytic reactions (CO oxidation, CO2 hydrogenation etc.). The work will focus on the development of new experimental procedures capable of monitoring the composition of the surface and nanostructures during reactions in real-time.
Neuromodulation technologies rely on electrical stimulation of the nervous system, and are used both in fundamental research and in numerous medical applications. Wireless stimulation devices, powered by tissue-penetrating deep red and infrared light wavelengths, can enable minimally-invasive solutions without wires and interconnects. This project involves fabrication and testing of light-powered neurostimulation, with a focus on maximizing efficiency while reducing the size of devices. An important parameter is the formation of a low-impedance electrical contact with the neural tissue. The project involves micro and nanofabrication, with a focus on semiconductor materials and electronics, while also involving advanced electrochemical and photoelectrochemical measurements. Collaboration with neuroscientists and participation in animal studies is envisioned as an important aspect of the project.
X-ray micro computed tomography is becoming one of the commonly used imaging methods in the fields of developmental biology and other biological disciplines. In the native sample only the mineralised bones are visible in the microCT scan, the visualization of the soft tissues requires the staining of the sample in the solutions of elements with high proton number. When the scans of the same sample in native and stained condition is combined the time-consuming process of segmenting the mineralised bones from the stained dataset can be skipped, this new approach enables much faster method of analysing the complex biological samples. In the scope of this work the optimising of the staining method of soft tissues and co-registration of both stained and native scans of same sample will be performed.
2D materials for batteries. Candidate will be trained in 2D materials fabrication and applications. MXenes, and black phosphorus materials will be in the focus. Candidate will learn how to use different technologies of 2D materials to achieve desired battery design. He/she will learn how to prepare high performance batteries.
2D materials of functional devices for supercapacitors. Candidate will be trained in 2D materials. Candidate will learn how to use different technologies of 2D materials to achieve desired supercapacitor design. He/she will learn how to prepare high performance supercapacitors.
Supercapacitors (SCs) represent one of the most promising energy storage technologies because of their remarkable features, such as ultrahigh power density and ultralong cycling life. This PhD study aims at an exploration of 2D hybrids based on MXenes and black phosphorous (BP), as high-performance electrode materials for SCs. It will concentrate on (i) multi-scale characterization of 2D hybrids up to atomic resolution to provide fundamental knowledge underlying the interaction between the components of 2D hybrids, and on (ii) an in situ study of chemical stability and growth mechanisms of these materials. In the study, state-of-the-art characterisation methods available at CEITEC Nano core facility such as Low Energy Electron Microscopy (LEEM), UHV STM/AFM, X-ray Photo-electron Spectroscopy (XPS), Low Energy Ion Scattering (LEIS), Scanning Auger Microscopy (SAM), FT-IR Spectroscopy, and HR (S)TEM will be used. The collaboration with the Dresden University of Technology planned to synthesize the 2D materials will be held.
This thesis will focus on the fabrication of new 2D materials for water treatment and purification.
The dissertation thesis will deal with the development of 3D epitaxial printing using eutectic liquid droplets, which are moved by electron beam (electron tweezers) in the UHV-SEM microscope, developed in cooperation with TESCAN. During the movement, the gold-containing droplet is saturated with germanium (silicon) atoms, resulting in epitaxial deposition of the semiconductor at the droplet location. The movement of the droplet and thus also the "print" location of the semiconductor can be controlled programmatically. Part of the work will be optimization of this process including its real-time monitoring using UHV-SEM microscope.
Microelectrodes are a very important element for neurostimulation and recording of neurological signals in the body. The properties of these electrodes significantly affect their performance, safety, and reliability. In terms of long-term implants, the most important is the lifespan in the physiological environment, which is currently the biggest problem of various implants for neurostimulation. This work will focus on the study and development of next-generation electrode systems that will be characterized by long-term stability and excellent electrical properties at the interface with the environment.
Tutor: Gablech Imrich, Ing., Ph.D.
3D printing of batteries. Candidate will be trained in 3D printing. Candidate will learn how to use different technologies of 3D printing to achieve desired battery design. He/she will learn how to prepare high performance batteries.
3D printing for devices for hydrogen evolution. Candidate will be trained in 3D printing. Candidate will learn how to use different technologies of 3D printing to achieve desired water electrolyzer design. He/she will learn how to prepare high performance electrolyzers for hydrogen evolution.
3D printing of functional devices for supercapacitors. Candidate will be trained in 3D printing. Candidate will learn how to use different technologies of 3D printing to achieve desired supercapacitor design. He/she will learn how to prepare high performance supercapacitors.
The work will focus on the preparation of porous and nanofiber scaffolds with different morphological, mechanical and biological properties so as to imitate different layers of skin in its entire thickness. The materials will be seeded with stem cells in order to create a full-fledged vascularized skin replacement. The samples will also be characterized in terms of biodegradation in physiological conditions, mechanical properties, morphology, swelling, as well as angiogenesis evaluated by the ex-ovo method, cytotoxicity and stem cell differentiation using an in vitro assay. In the final, the mounted carriers will be tested on an animal model of a pig.
X-ray computed tomography (CT) as a non-destructive inspection method offers a data information quality which can contribute a tremendous value to Industry 4.0. Current trend in the industrial CT, therefore, is the incorporation of this technology into the in-line manufacturing processes for the tasks such as the automated quality control and inspection of the goods. However, demanding technological aspects of hardware automatization and communication need to be resolved first. The new 5G communication standard enables highly reliable, secure and high-speed data transmission with short response times, making manufacturing more flexible, mobile and productive. Therefore, 5G forms an essential prerequisite for automatization and communication tasks in the industrial practise. This work addresses the practical implementation of 5G technology into devices used in in-line manufacturing lines with specific focus on significantly increasing autonomy, robustness and speed in industrial CT in order to support its transition towards a fully in-line quality assurance technology as required in Industry 4.0 environments.
Study plan wasn't generated yet for this year.