# Relativistic Classical and Quantum Nonlinear Phenomena in the Induced Processes on Free Electrons

## TL;DR

This review discusses recent advances in relativistic laser interactions with matter, highlighting nonlinear quantum electrodynamic phenomena and their implications for high-energy physics and laser-plasma applications.

## Contribution

It provides a comprehensive overview of nonlinear induced processes in free electrons under high-intensity radiation fields, emphasizing new experimental and theoretical insights.

## Key findings

- Observation of nonlinear QED phenomena at ultrahigh laser intensities
- Analysis of induced Cherenkov, Compton, and undulator processes
- Identification of threshold nonlinear resonances in electron dynamics

## Abstract

With the appearance of superpower laser sources of relativistic/ultrarelativistic intensities in the last decade, the laser-QED-vacuum-matter interaction physics has entered a new phase that makes real the observation of many nonlinear quantum electrodynamic (QED) and classical-quantum- mechanical phenomena revealed more than fore-five decades ago, serious advance in new generation of laser-plasma accelerators of ultrahigh energies, nuclear fusion etc. Hence, the present review article will help explorers-experimentalists in this field to attract attention on the fundamental properties and peculiarities of the dynamics of induced free-free transitions at high and superhigh intensities of stimulated radiation fields. In this connection it is of special interest the induced Cherenkov, Compton, undulator/wiggler coherent processes, as well as cyclotron resonance in a medium -- possessing with nonlinear resonances of threshold nature and leading to many important nonlinear effects or applications, which are considered in this review.