Interference in nonlinear Compton scattering using a Schr\"odinger's equation approach

TL;DR

This paper investigates the interference effects between Compton and nonlinear Compton scattering in a two-color X-ray field for bound electrons, using both perturbative and non-perturbative approaches to analyze phase shifts.

Contribution

It introduces a comparative analysis of perturbative and non-perturbative methods to study interference in nonlinear Compton scattering with different polarization configurations.

Findings

Interference occurs only in specific polarization cases.

Phase difference between waves is either 0 or π depending on scattering angle.

Perturbative approach is validated against non-perturbative calculations.

Abstract

The interference between Compton scattering and nonlinear Compton scattering from a two-color field in the X-ray regime is theoretically examined for bound electrons. The underlying phase shifts are analysed using a perturbative approach in the incoming classical field. The perturbative approach is bench marked with a non-perturbative approach in the classical field. The interference for different combinations of linear polarization of the two fields is examined when the Compton and the nonlinear Compton scattered waves have the same wave vector and polarization. Only two cases exhibit interference. When there is interference, the calculations reveal an intrinsic phase difference between the Compton scattered wave function and the nonlinear Compton scattered wave function of either 0 or $\pi$ depending on the scattering angle.