Photon-stimulated production of electron-positron pairs in electric field

TL;DR

This paper calculates the rate of electron-positron pair production induced by photons in a weak electric field, revealing a non-trivial dependence on photon energy and field strength through a semi-classical approach.

Contribution

It introduces a novel semi-classical method to compute pair production rates for sub-threshold photon energies in weak electric fields.

Findings

Pair production rate depends non-trivially on photon energy and field strength ratio.

Method based on thermal bath calculation and single-photon state contribution.

Results applicable for photon energies much below the electron mass and weak fields.

Abstract

The rate of $e^+e^-$ pair creation by external electric field in the presence of an incident photon beam is calculated for the photon energy far below the threshold, $\omega \ll m$, and the field strength small as compared to the critical one, $e E \ll m^2$. We find the pair production rate using a recently developed method based on calculation of the process in a thermal bath with subsequent identification of the contribution of single-photon states. We demonstrate that a non-trivial dependence on the ratio of the small parameters, $\omega m/(e E)$, emerges in this approach from an essentially (semi)classical calculation.