Absorption and Emission in a Free Electron Lasers

TL;DR

This paper investigates how strong magnetic fields in free electron lasers can significantly increase the frequency of emitted radiation while maintaining high gain, by analyzing multiphoton processes and calculating absorption, emission, and gain.

Contribution

It introduces a method to enhance free electron laser frequencies using strong magnetic fields in undulators, with detailed calculations of absorption, emission, and gain.

Findings

Strong magnetic fields enable higher frequency amplification.

Gain remains substantial despite increased frequencies.

Absorption and emission probabilities are quantitatively analyzed.

Abstract

Multiphoton processes in undulators with plane polarized magnetic field are considered. It is shown that the use of strong magnetic fields in the undulator, for beams with relatively low energy makes it possible to increase substantially the frequencies of the amplified electromagnetic waves without noticeably decreasing the gain. The absorption, emission probabilities and the gain are calculated.