Nonlinear double Compton scattering in the full quantum regime

TL;DR

This paper analyzes nonlinear double Compton scattering in the full quantum regime using strong-field QED, revealing how photon recoil affects emission spectra and proposing experimental feasibility with current technology.

Contribution

It provides a comprehensive quantum analysis of double photon emission in intense laser fields, including exact laser field effects and a semiclassical explanation of spectral differences.

Findings

Photon recoil significantly alters emission spectra.

Feasibility of experimental observation with current technology.

Semiclassical trajectory-based explanation for spectral differences.

Abstract

A detailed analysis of the process of two photon emission by an electron scattered from a high-intensity laser pulse is presented. The calculations are performed in the framework of strong-field QED and include exactly the presence of the laser field, described as a plane wave. We investigate the full quantum regime of interaction, where photon recoil plays an essential role in the emission process, and substantially alters the emitted photon spectra as compared to those in previously-studied regimes. We provide a semiclassical explanation for such differences, based on the possibility of assigning a trajectory to the electron in the laser field before and after each quantum photon emission. Our numerical results indicate the feasibility of investigating experimentally the full quantum regime of nonlinear double Compton scattering with already available plasma-based electron accelerator and laser technology.