Quantum electron self-interaction in a strong laser field

TL;DR

This paper investigates how an electron's quantum state in a strong laser field is modified by its own electromagnetic self-interaction, revealing quantum contributions to its momentum and spin dynamics that could be experimentally observed.

Contribution

It introduces a leading-order analysis of electron self-interaction effects in a plane-wave laser field starting from the Schwinger-Dirac equation, highlighting quantum effects absent in classical models.

Findings

Electron states exhibit a quantum contribution to quasi-momentum.

Self-interaction affects electron spin dynamics.

Effects are potentially measurable with current technology.

Abstract

The quantum state of an electron in a strong laser field is altered if the interaction of the electron with its own electromagnetic field is taken into account. Starting from the Schwinger-Dirac equation, we determine the states of an electron in a plane-wave field with inclusion, at leading order, of its electromagnetic self-interaction. On the one hand, the electron states show a pure "quantum" contribution to the electron quasi-momentum, conceptually different from the conventional "classical" one arising from the quiver motion of the electron. On the other hand, the electron self-interaction induces a distinct dynamics of the electron spin, whose effects are shown to be measurable in principle with available technology.