Eur. Phys. J. D (2022) 76: 63
https://doi.org/10.1140/epjd/s10053-022-00389-4

Regular Article – Quantum Optics

The linear and nonlinear inverse Compton scattering between microwaves and electrons in a resonant cavity

¹ Institute of High Energy Physics, Chinese Academy of Sciences, 100049, Beijing, China
² University of Chinese Academy of Sciences, 100049, Beijing, China
³ School of Science, Shenzhen Campus of Sun Yat-sen University, 518107, Shenzhen, People’s Republic of China
⁴ Physics and Space Science College, China West Normal University, 637009, Nanchong, China
⁵ National Synchrotron Radiation Laboratory, University of Science and Technology of China, 230029, Hefei, China
⁶ State Key Laboratory of Particle Detection and Electronics, Institute of High Energy Physics, CAS, 100049, Beijing, China

^c huangysh59@mail.sysu.edu.cn

Received: 17 January 2022
Accepted: 22 March 2022
Published online: 1 April 2022

Abstract

The new scheme of the energy measurement of the extremely high energy electron beam with the inverse Compton scattering between electrons and microwave photons requires the precise calculation of the interaction cross section of electrons and microwave photons in a resonant cavity. In the local space of the cavity, the electromagnetic field is expressed by Bessel functions. Although Bessel functions can form a complete set of orthogonal basis, it is difficult to quantify them directly as fundamental wave functions. Fortunately, with the Fourier expansion of Bessel functions, the local electromagnetic field can be considered as the superposition of a series of plane waves. Therefore, with corresponding corrections of the cross section formula of the classical Compton scattering, the cross section of the linear or nonlinear microwave Compton scattering in the local space can be described accurately. As an important application of our results in astrophysics, corresponding ground verification devices can be designed to perform experimental verifications on the prediction of the Sunyaev–Zeldovich (SZ) effect of the cosmic microwave background radiation. Our results could also provide a new way to generate wave sources with strong practical value, such as the terahertz waves, the ultra-violet (EUV) waves, or the mid-infrared beams.