Publication detail

Probing the electromagnetic response of dielectric antennas by vortex electron beams

KONEČNÁ, A. SCHMIDT, M. HILLENBRAND, R. AIZPURUA, J.

Original Title

Probing the electromagnetic response of dielectric antennas by vortex electron beams

Type

journal article in Web of Science

Language

English

Original Abstract

Focused beams of electrons, which act as both sources and sensors of electric fields, can be used to characterize the electric response of complex photonic systems by locally probing the induced optical near fields. This functionality can be complemented by embracing the recently developed vortex electron beams (VEBs), made up of electrons with orbital angular momentum, which could, in addition, probe induced magnetic near fields. In this work we revisit the theoretical description of this technique, dubbed vortex electron energy-loss spectroscopy (v-EELS). We map the fundamental, quantum-mechanical picture of the scattering of the VEB electrons to the intuitive classical models, which treat the electron beams as a superposition of linear electric and magnetic currents. We then apply this formalism to characterize the optical response of dielectric nanoantennas with v-EELS. Our calculations reveal that VEB electrons probe electric or magnetic modes with different efficiency, which can be adjusted by changing either beam vorticity or acceleration voltage to determine the nature of the probed excitations. We also study a chirally arranged nanostructure, which in the interaction with electron vortices produces dichroism in electron-energy-loss spectra. Our theoretical work establishes VEBs as versatile probes that could provide information on optical excitations otherwise inaccessible with conventional electron beams.

Keywords

ENERGY-LOSS; LIGHT-SCATTERING; MIE RESONANCES; MODES; SURFACE; EXCITATIONS; ABSORPTION; GENERATION; EMISSION; SPHERE

Authors

KONEČNÁ, A.; SCHMIDT, M.; HILLENBRAND, R.; AIZPURUA, J.

Released

26. 6. 2023

Publisher

AMER PHYSICAL SOC

Location

COLLEGE PK

ISBN

2643-1564

Periodical

Physical Review Research

Year of study

5

Number

2

State

United States of America

Pages from

1

Pages to

16

Pages count

16

URL

https://journals.aps.org/prresearch/abstract/10.1103/PhysRevResearch.5.023192

Full text in the Digital Library

http://hdl.handle.net/11012/244958

BibTex

@article{BUT184844,
  author="Andrea {Konečná} and Mikolaj K. {Schmidt} and Rainer {Hillenbrand} and Javier {Aizpurua}",
  title="Probing the electromagnetic response of dielectric antennas by vortex electron beams",
  journal="Physical Review Research",
  year="2023",
  volume="5",
  number="2",
  pages="1--16",
  doi="10.1103/PhysRevResearch.5.023192",
  issn="2643-1564",
  url="https://journals.aps.org/prresearch/abstract/10.1103/PhysRevResearch.5.023192"
}