Two-photon Compton process in pulsed intense laser fields

TL;DR

This paper derives a compact formula for the two-photon Compton process in pulsed intense laser fields using strong-field QED, revealing that the process is significantly more probable than perturbative estimates suggest.

Contribution

It introduces a new analytical expression for the two-photon emission probability in pulsed laser fields, accounting for finite pulse effects and intermediate state regularization.

Findings

Two-photon emission spectrum is two orders of magnitude stronger than perturbative predictions.

Finite laser pulse duration naturally regularizes on-shell contributions.

Derived a relation between real and virtual intermediate states in the process.

Abstract

Based on strong-field QED in the Furry picture we use the Dirac-Volkov propagator to derive a compact expression for the differential emission probability of the two-photon Compton process in a pulsed intense laser field. The relation of real and virtual intermediate states is discussed, and the natural regularization of the on-shell contributions due to the finite laser pulse is highlighted. The inclusive two-photon spectrum is two orders of magnitude stronger than expected from a perturbative estimate.