Manipulating Cherenkov Radiation and Smith–Purcell Radiation by Artificial Structures

Abstract

A moving charged particle, such as an electron, can radiate light due to the interaction between its Coulomb field and surrounding matter. This phenomenon has spawned great interest in the fields of physics, electron microscopy, optics, biology, and materials science. Since the radiation generated by the charged particles strongly depends on the surrounding matter, artificially engineered materials with exotic electromagnetic and optic properties, including metamaterials and metasurfaces, provide an unprecedented opportunity to tailor the interaction between the charged particle and matter, and ultimately enable to manipulate the radiated light. In this review, the fundamentals of Cherenkov radiation and Smith–Purcell radiation are presented. Subsequently, the recent advances in the control of Cherenkov radiation and Smith–Purcell radiation based on metamaterials and metasurfaces are summarized. Finally, the applications using these two physical phenomena, including electron‐driven photon sources and electron accelerators, are discussed in this review.

Controlling the degrees of freedom in metasurface designs for multi-functional optical devices

“…Finally, more interesting physical systems, such as paritytime symmetry, [189][190][191] Smith-Purcell emission, [192][193][194][195] 2D materials [196][197][198] and topology, [199][200][201] could be introduced as a new DOF. For these research areas, metasurfaces provide an unprecedented opportunity to tailor their inner properties.…”

Control of quantum electrodynamical processes by shaping electron wavepackets

“…The useful range of electron kinetic energies runs the gamut from non-relativistic energies, as low as 50 eV in applications like coherent low-energy electron microscopy 5 – 10 , to ultra-relativistic energies, as high as several GeV in X-ray free electron laser facilities 11 , 12 . Broader applications of free electron sources include electron beam lithography 13 , 14 , atom-by-atom matter assembly 15 , nanoscale radiation sources 16 – 36 , and electron microscopy 37 – 47 .…”

Free-Electron Radiation Engineering via Structured Environments

“…The wide variety of structured materials provides powerful tools to control emission behaviors of free-electron radiation that leads to many significant findings [15][16][17][18][19][20][21][22][23]. Simply within the topic of Cherenkov radiation, the relevant studies have continuously demonstrated new phenomena include nondivergent [24], threshold-free [25] and reversed Cherenkov radiation [26].…”