Cherenkov radiation generated in hexagonal boron nitride using extremely low-energy electrons

Nanophotonics

Zhang Wei¹  Lin Yuechai¹  Feng Xue¹  Qu Tuo¹  Huang Yidong¹  Liu Fang¹  Cui Kaiyu¹ 

[1] Department of Electronic Engineering, Tsinghua University, Beijing, 100084, PR China;

关键词: cherenkov radiation;    hexagonal boron nitride (hbn);    hyperbolic materials;    phonon polaritons;   

DOI  :  10.1515/nanoph-2020-0090

来源: DOAJ

【 摘 要 】

Cherenkov radiation (CR) is the electromagnetic shockwaves generated by the uniform motion of charged particles at a velocity exceeding the phase velocity of light in a given medium. In the Reststrahlen bands of hexagonal boron nitride (hBN), hyperbolic phonon polaritons (HPPs) are generated owing to the coupling between mid-infrared electromagnetic waves and strong anisotropic lattice vibrations. This study theoretically and numerically investigates the generation of volume CR based on HPPs in hBN with super-large wavevectors. Results reveal that CR can be generated using free electrons with an extremely low kinetic energy of 1 eV—two orders of magnitude lower than that reported in extant studies. The findings of this investigation provide new insights into significantly reducing the electron energy required for CR generation and potentially open new research avenues in the fields of CR and HPP.

【 授权许可】

Unknown