Self-amplified Cherenkov radiation from a relativistic electron in a waveguide partially filled with a laminated material

TL;DR

This paper investigates Cherenkov radiation from a relativistic electron in a cylindrical waveguide filled with laminated materials, revealing conditions for self-amplification of the radiation and discussing potential applications.

Contribution

It derives general expressions for spectral radiation distribution in laminated waveguides without permittivity or permeability limitations, and demonstrates self-amplification of Cherenkov radiation under specific parameters.

Findings

Cherenkov radiation can be self-amplified in laminated waveguides.

Derived spectral distribution formulas applicable to arbitrary layered media.

Identified parameter conditions for radiation amplification.

Abstract

The radiation from a relativistic electron uniformly moving along the axis of cylindrical waveguide filled with laminated material of finite length is investigated. Expressions for the spectral distribution of radiation passing throw the transverse section of waveguide at large distances from the laminated material are derived with no limitations on the amplitude and variation profile of the layered medium permittivity and permeability. Numerical results for layered material consisting of dielectric plates alternated with vacuum gaps are given. It is shown that at a special choice of problem parameters, Cherenkov radiation generated by the relativistic electron inside the plates is self-amplified. The visual explanation of this effect is given and a possible application is discussed.