Full-time study

4 years

prof. RNDr. Tomáš Šikola, CSc.

Chairman :
prof. RNDr. Tomáš Šikola, CSc.
Councillor internal :
prof. RNDr. Petr Dub, CSc.
prof. RNDr. Radim Chmelík, Ph.D.
prof. Ing. Ivan Křupka, Ph.D.
prof. RNDr. Pavel Šandera, CSc.
Councillor external :
RNDr. Antonín Fejfar, CSc.
prof. Mgr. Dominik Munzar, Dr.
prof. RNDr. Pavel Zemánek, Ph.D.

The aim of the doctoral study in the proposed programme is to prepare highly educated experts in the field of physical engineering and nanotechnology with sufficient foreign experience, who will be able to perform independent creative, scientific and research activities in academia or applications in our country and abroad. The study is based on the doctoral students' own creative and research work at the level standardly required at foreign workplaces in the areas of research carried out at the training workplace and supported by national and international projects. These are the following areas of applied physics: physics of surfaces and nanostructures, light and particle optics and microscopy, construction of physical instruments and equipment, micromechanics of materials.

The graduate has knowledge, skills and competencies for their own creative activities in some of the areas in which the research activities of the training workplace are carried out. These are applications of physics especially in the field of physics of surfaces and nanostructures, two-dimensional materials, nanoelectronics, nanophotonics, micromagnetism and spintronics, biophotonics, advanced light microscopy and spectroscopy, electron microscopy, laser nanometrology and spectroscopy, computer controlled X-ray micro and nanotomography, micro and development of technological and analytical equipment and methods for micro/nanotechnologies. The possibility of using the personnel and material background provided by the CEITEC research infrastructure as well as extensive cooperation with important foreign workplaces contributes to the high level of education. This guarantees that the graduate is able to present the results of their work orally and in writing and discuss them in English. Due to high professional competencies and flexibility, graduates find employment both in universities and other research institutions in our country and abroad, and in high-tech companies in the positions of researchers, developers, designers or team leaders.

Due to their high professional competencies and flexibility, graduates find employment in the field of basic and applied research at universities and other research institutions in our country and abroad, as well as in high-tech companies in the positions of researchers, developers, designers and team leaders.

See applicable regulations, DEAN’S GUIDELINE Rules for the organization of studies at FME (supplement to BUT Study and Examination Rules)

The rules and conditions of study programmes are determined by:
BUT STUDY AND EXAMINATION RULES
BUT STUDY PROGRAMME STANDARDS,
STUDY AND EXAMINATION RULES of Brno University of Technology (USING "ECTS"),
DEAN’S GUIDELINE Rules for the organization of studies at FME (supplement to BUT Study and Examination Rules)
DEAN´S GUIDELINE Rules of Procedure of Doctoral Board of FME Study Programmes
Students in doctoral programmes do not follow the credit system. The grades “Passed” and “Failed” are used to grade examinations, doctoral state examination is graded “Passed” or “Failed”.

Brno University of Technology acknowledges the need for equal access to higher education. There is no direct or indirect discrimination during the admission procedure or the study period. Students with specific educational needs (learning disabilities, physical and sensory handicap, chronic somatic diseases, autism spectrum disorders, impaired communication abilities, mental illness) can find help and counselling at Lifelong Learning Institute of Brno University of Technology. This issue is dealt with in detail in Rector's Guideline No. 11/2017 "Applicants and Students with Specific Needs at BUT". Furthermore, in Rector's Guideline No 71/2017 "Accommodation and Social Scholarship“ students can find information on a system of social scholarships.

The presented doctoral study programme represents the highest level of education in the field of physical engineering and nanotechnology. Follows the academic and bachelor's and subsequent master's degree programme of "Physical Engineering and Nanotechnology", which are carried out at FME BUT.

1. Advanced optical materials and nanostructures

   Advanced functional materials are a class of novel materials with unique optical properties and promising application potential. The PhD study will involve optical characterization of these materials using high lateral resolution techniques. The results will be compared with other correlative methods measuring topography, chemical composition, crystallographic arrangement, etc.

   Tutor: Spousta Jiří, prof. RNDr., Ph.D.

2. Advanced scanning probe microscopy of functional materials and nanostructures

   The work will deal with the development of unique multifunctional SPM probes of the new generation, which are currently being developed at ÚFI FSI as part of the ending TAČR Trend (INCHAR) project. These probes will be used both for preparation and simultaneous characterization of nanostructures in the electron microscope chamber (topography, optical and electrical properties, etc.). The uniqueness of the new generation probe lies in the ability to bring voltage, working medium and intense laser light under the tip, which represents a significant scientific and technological challenge. The focus of the work will be on determining a portfolio of suitable technological procedures for the preparation of nanostructures using the aforementioned functionalities and their further development. It can be, for example, i) a modified LAO (Local Anodic Oxidation) method, ii) the preparation of nanowires by the VLS (Vapor Liquid Solid) method in UHV conditions, iii) the production of new tools for the preparation of nanostructures, (e.g. a microeffusion cell suitable for the deposition of metal i non-conductive nanostructures, deposition (Ga, perovskite, etc.) from the liquid phase, etc.). All these possible methods of preparation and characterization of nanostructures must allow simultaneous (correlated) observation in an electron microscope - CPEM (Correlative Probe and Electron Microscopy), which will again be very difficult to achieve due to the current state of electron detection by photomultipliers (the light in the microscope chamber significantly interferes with this detected signal). The basis will be the use of the NenoVision LiteScope microscope, in the development of which the doctoral student will participate as part of his doctoral studies.

   Tutor: Spousta Jiří, prof. RNDr., Ph.D.

3. Advanced 3D reconstruction of microscopic data

   Electron microscopy with subatomic resolution, 3D and 4D imaging techniques are indispensable tools in the study of the function and structure of objects from live and material science. High-resolution STEM data capture techniques and ptychorgraphic (diffractive) reconstructions enable electron microscopy analysis at very low doses that eliminate radiation damage of the investigated samples. Another advanced method for 3D imaging is FIB-SEM finding applications in biology and material sciences. These techniques require sophisticated and complex data processing. The student's dissertation will mainly focus on developing simulation and computational methods using neural networks and AI. The aim of the thesis will be an approach for spatial reconstruction using ptychographic data. The project will be carried out at the Institute of Instrumentation Technology (IIT) of the Czech Academy of Sciences with the possibility of part/full time employment. The Ph.D. student will be a member of several TAČR and GAČR type projects currently underway at the Institute.

   Tutor: Krzyžánek Vladislav, Ing., Ph.D.

4. Application of electron beam lithography in micro-electromechanical systems

   As a part of this doctoral thesis, micro-electromechanical systems (MEMS) devices will be fabricated by a combination of electron beam lithography (EBL) and deep etching procedures enabling high degree of accuracy and control. The devices will be focused on sensors, actuators and microfluidic cells, e.g. pressure, tension, and flow sensors. The devices will be operationally tested and simultaneously or separately characterized by advanced analytical techniques: scanning probe microscopy (SPM), scanning electron microscopy (SEM), Raman spectroscopy and transport measurements. Devices will be specified with regard to projects solved in cooperation with the company Thermo Fisher Scientific and related to their contribution in the field of basic research and their publication impact.

   Tutor: Bartošík Miroslav, doc. Ing., Ph.D.

5. Applications of shaped electron beams

   In this project, the PhD candidate will study applications shaped beams in electron microscopy and spectroscopy. The student will focus on fast and damage-free imaging and spectroscopy, probing low-energy excitations beyond the usual selection rules and studying optical dichroism, everything down to the atomic scale.

   Tutor: Konečná Andrea, doc. Ing., Ph.D.

6. Applications of shaped electron beams

   In this project, the PhD candidate will study applications shaped beams in electron microscopy and spectroscopy. The student will focus on fast and damage-free imaging and spectroscopy, probing low-energy excitations beyond the usual selection rules and studying optical dichroism, everything down to the atomic scale.

   Tutor: Konečná Andrea, doc. Ing., Ph.D.

7. Atomically-thin Metasurface Optics based on High Performance 2D materials

   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.

   Tutor: Šikola Tomáš, prof. RNDr., CSc.

8. BICs in periodic nanophotonic systems

   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 several interesting applications; for example, in photonics, BICs enable development of sensitive nanostructures with significant reduction of radiation leakage [1,2]. The study will focus on theoretical analysis and physical understanding of BICs in periodic nanophotonic systems, such as photonic crystals or metasurfaces, which can be used, e.g., for advanced biosensing [3]. The student will explore the existence and properties of the BICs in a selected class of the systems. Critical assessment of the benefits of the BICs in comparison with more traditional techniques from the point of view of potential sensing applications will be carried out. The study will rely heavily on numerical analysis. [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] M. L. Tseng, Y. Jahani, A. Leitis, and H. Altug, “Dielectric Metasurfaces Enabling Advanced Optical Biosensors,” ACS Photonics, vol. 8, no. 1, pp. 47–60, 2021.

   Tutor: Petráček Jiří, prof. RNDr., Dr.

9. BICs in photonic waveguides

   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 several interesting applications; for example, in photonics, BICs enable development of sensitive nanostructures with significant reduction of radiation leakage [1,2]. Even though the first observation of photonic BIC was achieved in a system of coupled waveguides [3], the individual waveguides supported conventional modes outside the radiation continuum. Researchers have observed BICs in a single waveguide with a low-index core; however, effectively such a waveguide acts as a conventional quantum well (i.e., localization in the region with high effective refractive index). Therefore, the study will address this problem and focus on theoretical investigation of various possible alternative mechanisms that could enable BICs in waveguides. As a starting point anisotropy induced BICs in dielectric waveguides will be studied. Subsequently, more general class of waveguide structures will be considered; namely, we will assume nanophotonic waveguide structures and perform systematic parametric studies to explore the existence of new BICs. Finally, critical assessment of the benefits of the BICs in comparison with classical guided waves from the point of view of their potential integrated photonic applications will be carried out. [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 [4] Y. Yu, et al., “Ultralow-Loss Etchless Lithium Niobate Integrated Photonics at Near-Visible Wavelengths,” Adv. Opt. Mater., vol. 9, no. 19, pp. 1–8, 2021.

   Tutor: Petráček Jiří, prof. RNDr., Dr.

10. Corrector of optical aberrations of the electron microscope

    Rotationally symmetric electromagnetic lenses used for imaging in electron microscopy are burdened by imaging aberrations that limit their resolution. Several physical principles have been described in the literature, which make it possible to correct aberrations of electromagnetic lenses. Image correction can be achieved, for example, by a multi-pole electromagnetic field, a phase plate formed by a solid substance or field, an electrostatic mirror and others. Correction systems have been successfully implemented on some types of electron microscopes (e.g. a hexapole corrector for a spherical aberration in a transmission microscope). The dissertation will be focused on the methodology of correction of imaging aberrations and the design of a correction system for an electron microscope in cooperation with the company TESCAN.

    Tutor: Zlámal Jakub, Ing., Ph.D.

11. Correlative analysis of wide band gap materials

    Wide band gap materials are in the center of current technological advancement in power electronics, mostly due to recently developed fabrication techniques of bulk crystals. Most importantly, SiC and GaN have started to question silicon use in certain applications. However, compared to silicon, current know-how of relevant properties of these materials is not mature enough. Student will focus on analysis of defects in SiC and GaN by correlative micro- and spectroscopies. A part of the work is a realization of proof-of-concept device in electronics/optoelectronics. A necessary prerequisite is solid knowledge of solid state physics and principles of relevant spectroscopic techniques. The research will be conducted in collaboration with Thermo Fisher Scientific or Onsemi. Students are strongly advised to contact the supervisor before the official admission interview.

    Tutor: Kolíbal Miroslav, prof. doc. Ing., Ph.D.

12. Deposition of nanocrystals on graphene substrate

    GaN nanocrystals appear to be very promising for use in the preparation of UV sensors, especially because of their broad direct bandgap (3.4 eV). In combination with a graphene conductive layer, a very efficient UV sensor can be obtained. The growth of GaN nanocrystals on a graphene substrate suitable for UV sensor preparation will be studied during the PhD. In addition, the effect of metal nanoparticles on the sensor surface on its properties (sensitivity, reaction time, ...) will be studied.

    Tutor: Mach Jindřich, doc. Ing., Ph.D.

13. Deposition of semiconductor nanostructures by MBE

    Semiconductor nanocrystals (Ga2O3, GaN. AlN,...) appear to be very promising for use in the semiconductor industry, especially due to their broad direct bandgap. The growth of semiconductor nanocrystals will be studied by using the droplet epitaxy method. In this method, metal droplets are prepared on a substrate in the first stage of the process, which are subsequently transformed into semiconductor nanostructures due to the interaction of atomic (ion) beams. Physical properties of nanostructures will be studied.

    Tutor: Mach Jindřich, doc. Ing., Ph.D.

14. Design and Fabrication of Dielectric Metasurfaces for Unconventional Optical Elements

    The dissertation will focus on the design and fabrication of dielectric metasurfaces for unconventional optical elements in the ultraviolet, visible, and infrared wavelength regions. Specific metasurface design methods using optimization algorithms with multiparametric metrics, such as the Gerchberg-Saxton algorithm, will be explored. Fabrication approaches, including electron beam lithography, dry etching, and various deposition techniques for preparing dielectric layers, will also be investigated. Additionally, simulations of individual metasurface building blocks will be an integral part of the research. The main goal of this work is to produce fully characterized prototypes of metasurfaces with verified functionalities, which could be used for shaping high-performance optical beams or in the transmission and processing of optical signals in communication technologies.

    Tutor: Šikola Tomáš, prof. RNDr., CSc.

15. Electron beam energy filter

    Electron sources used in electron microscopes generate a beam with an energy distribution whose width is characteristic of the given source. The low energy dispersion is advantageous for microscopic techniques, because especially at low accelerating voltage, the contribution of the chromatic aberration is a significant factor limiting the resolution. The aim of the dissertation will be the design of an energy filter for the electron beam, which will enable the narrowing of the energy distribution in the electron beam emitted from the Schottky source and its realization in cooperation with the TESCAN company.

    Tutor: Zlámal Jakub, Ing., Ph.D.

16. Electron microscopy and analysis of van der Waals materials

    The PhD study will be aimed at characterization of van der Waals materials and measurement of their functional properties. It will especially cover new types of these materials such as MXenes, their multilayers with TMDs, as well as 2D perovskites. As the major investigation tool, electron microscopy will be applied, namely a newly developed 4D STEM with FIB for fabrication and in situ analysis of lamellas of these materials, as well as HR (S)TEM for getting atomically resolved information. This will enable to study structure (electron diffraction), composition (EDS, EELS) and selected functional properties (e.g. localized surface plasmons and their coupling with excitons) of these novel materials.

    Tutor: Šikola Tomáš, prof. RNDr., CSc.

17. Electron tweezers and development of new applications

    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: Průša Stanislav, doc. Ing., Ph.D.

18. GaN/Graphene-based detectors of UV radiation

    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).

    Tutor: Šikola Tomáš, prof. RNDr., CSc.

19. Generation and detection of THz spin waves by plasmonic antennas

    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).

    Tutor: Šikola Tomáš, prof. RNDr., CSc.

20. Growth or organic semiconductors on weakly interacting substrates

    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.

    Tutor: Čechal Jan, prof. Ing., Ph.D.

21. Growth or organic semiconductors on weakly interacting substrates

    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.

    Tutor: Čechal Jan, prof. Ing., Ph.D.

22. In-situ preparation and modification of two-dimensional nanostructures

    Revealing the growth mechanisms at nanoscale is particularly challenging from many reasons. The most prominent advances in physics of nanostructure growth were achieved utilizing real-time in-situ monitoring techniques (both microscopic and spectroscopic). In our group, we have a large expertise in real time electron microscopy. The aim of this PhD dissertation is to work on revealing puzzling growth modes of twodimensional nanostructures of interest (silicene, phosphorene, transition metal selenides etc.) utilizing state-of-the-art equipment, as well as study of their interaction with electrons, their oxidation and modification (e.g., formation of Janus monolayers).

    Tutor: Kolíbal Miroslav, prof. doc. Ing., Ph.D.

23. Localized plasmon-enhanced absorption upon strong coupling

    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.

    Tutor: Šikola Tomáš, prof. RNDr., CSc.

24. Machine-learned interatomic potentials for grain boundaries

    Machine learning is a novel and promising method to model interatomic interactions in a computationally efficient way. One of the research areas potentially suitable for application of such a method is the research of grain boundaries, particularly their strengthening or embrittlement due to segregated impurities. This PhD topic will cover generation and DFT (density functional theory) benchmarking of machine-learned potentials, their subsequent application to large-scale models of grain boundaries and testing their transferability.

    Tutor: Černý Miroslav, prof. Mgr., Ph.D.

25. Mapping plasmonic modes

    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).

    Tutor: Šikola Tomáš, prof. RNDr., CSc.

26. Metal-insulator transition probed by analytical electron microscopy

    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.

27. Metal-insulator transition probed by analytical electron microscopy

    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.

28. Miniaturized on-chip-setup for levitation and cooling of nanoobjects

    The PhD thesis will focus on the miniaturization of an assembly for levitation of nano-objects using machined optical fibers, surface microstructures and nanostructures. The goal is to create a functional chip to trap a nanoparticle, cool its mechanical motion modes, and find experimental limits to achieve the ground quantum state of the cooled nanoparticle. The PhD thesis will involve a unique experimental setup at the Institute of Scientific Instruments of the Czech Academy of Sciences in Brno (ISI), using advanced nanotechnologies at ISI and CEITEC laboratories in Brno. The PhD student is expected to perform experiments, analyze and interpret the results. The ISI will provide salary and material conditions for the work for a period of 4 years and international contacts of the PhD student with experts from world leading laboratories.

    Tutor: Jákl Petr, Ing., Ph.D.

29. Modeling of functional properties of nanostructures for plasmonics

    The topic includes the theoretical description of the optical response of metallic nanostructures and metasurfaces for applications in plasmonics and nanophotonics. Used calculation tools will be represented by both analytical methods (e.g. optical properties of layered systems illuminated by a monochromatic plane wave, decomposition of the optical response of nanoparticles into the normal or quasinormal modes, mathematics used in diffraction optics) and numerical methods by using available software packages (e.g. based on a finite-difference time-domain method, a finite-element frequency-domain method, rigorous coupled-wave analysis) or, possibly, by using home-made computational algorithms. The results will be used for the qualitative- and quantitative interpretation of experimental data.

    Tutor: Kalousek Radek, doc. Ing., Ph.D.

30. Numerical processing methods of experimental data for imaging spectroscopic reflectometry within the framework of the optical characterization of non-uniform thin solid films

    The content of the dissertation thesis is to find effective algorithms for numerical processing of big sets of experimental data obtained by means of imaging spectroscopic Reflectometer (built in The Coherence Optics Laboratory of IPE FME BUT) from non-uniform thin films for the determination of the optical parameters of these films. The goal is to realize aforementioned algorithms in the form of a software.

    Tutor: Ohlídal Miloslav, prof. RNDr., CSc.

31. Plasmonic lightning-rod effect

    Plasmonic antennas are conductive nanostructures allowing to enhance and concentrate light at the nanoscale. They often exploit the lightning-rod effect, a local enhancement of the electric field near sharply curved surfaces. Despite its importance in plasmonics, the effect is understood mostly intuitively: a comprehensive description of its fundamentals is missing. The thesis aims to provide such insight. Partial effects contributing to the overall lightning-rod effect will be investigated: plasmonic surface wave localization, the effect of the curvature, the effect of the charge reservoir, and the effect of plasmonic gap enhancement between two interacting plasmonic antennas. The methodology will be based on electromagnetic simulations and experimental techniques for the local field characterization. A detailed understanding of the lightning-rod effect will provide a guideline for the design of plasmonic antennas with particularly large field enhancement.

    Tutor: Křápek Vlastimil, doc. Mgr., Ph.D.

32. Semiclassical optomechanics with more nanoobjects

    The PhD thesis will experimentally develop a new and promising problem of cold nanoparticles levitating in vacuum and interacting with a laser beam in a controlled manner. The advantage of such an arrangement is that the interaction of the nanoparticles with the thermal environment is minimized and takes place dominantly through coherent photons of the laser beam or photons scattered by the particles. The distribution of photon flux in the laser beam can be controlled in space and time, thereby controlling the dynamics of the nanoparticles in space. In this way, mechanical energy can be removed from the nanoparticles and the amplitude of their deflections can be reduced to the interface between classical and quantum behaviour. The experimental system described here will allow the observation of a number of unique physical effects at the interface between classical and quantum physics, and points towards a novel realization of quantum technologies with objects much larger than atoms. The PhD thesis will implement a unique experimental setup at the Institute of Scientific Instruments of the Czech Academy of Sciences (ISI), which will allow to trap multiple nanoparticles, remove their mechanical energy and rapidly change the spatial distribution of intensity and phase in the trapping laser beams over time. The aim of this work will be to observe the behaviour of nanoparticles at the interface between classical and quantum physics. The PhD student is expected to perform experiments, analyze and interpret the results. The ISI will provide salary and material conditions for the work for a period of 4 years and international contacts of the PhD student with experts from world leading laboratories.

    Tutor: Brzobohatý Oto, Mgr., Ph.D.

33. Study and measurement of fast biomechanical reactions of living cells

    Digital holographic microscopy will be used for the comparative study of biomechanical reactions of living cells in-vitro. The study will use incoherent holographic imaging techniques in combination with a through-flow bioreactor. The work will also deal with the processing and analysis of image data, including numerical biomechanical simulations.

    Tutor: Chmelík Radim, prof. RNDr., Ph.D.

34. Use of imaging spectroscopic reflectometry for determining the optical parameters of non-uniform thin films

    The content of the work is the use of imaging spectroscopic reflectometers (built in the Laboratory of Coherence Optics ÚFI FME BUT) to determine the optical parameters of thin films non-uniform in these parameters, using already developed numerical algorithms for processing experimental data obtained by these reflectometers. The aim is to establish a methodology for the above procedure.

    Tutor: Ohlídal Miloslav, prof. RNDr., CSc.

35. Utilization of angle resolved scattering of light from randomly rough surfaces to determine the topographic parameters of these surfaces

    The content of the work is the use of angle resolved scattering (ARS) of light to determine the spectral power density (PSD) and associated parameters of the randomly rough surface topography using a new-generation SM3 scatterometer (Built in the Laboratory of Coherence Optics, FME BUT). The aim is to determine the methodology of the above procedure and to study the possibilities of using known theories of light scattering for different ranges of roughness of randomly rough surfaces

    Tutor: Ohlídal Miloslav, prof. RNDr., CSc.

36. Utilization of plasmonic nanostructures for local enhancement of magnetic components of electromagnetic fields

    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.

    Tutor: Šikola Tomáš, prof. RNDr., CSc.

37. 2D materials for 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.

    Tutor: Šikola Tomáš, prof. RNDr., CSc.

38. 3D epitaxial printing of semiconductors using electron tweezers

    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.

    Tutor: Průša Stanislav, doc. Ing., Ph.D.