Sauter-Schwinger pair creation dynamically assisted by a plane wave

TL;DR

This paper investigates how a weaker plane wave can enhance electron-positron pair creation in a strong electric field, using both non-perturbative and perturbative methods, revealing exponential enhancement under certain conditions.

Contribution

It demonstrates the agreement between non-perturbative and high-order perturbative approaches in analyzing the dynamically assisted Sauter-Schwinger effect.

Findings

Good agreement between methods when perturbative expansion is sufficiently high order

Exponential enhancement of pair creation probability occurs above a threshold Keldysh parameter

Plane wave assistance significantly boosts pair production in strong electric fields

Abstract

We study electron-positron pair creation by a strong and constant electric field superimposed with a weaker transversal plane wave which is incident perpendicularly (or under some angle). Comparing the fully non-perturbative approach based on the world-line instanton method with a perturbative expansion into powers of the strength of the weaker plane wave, we find good agreement - provided that the latter is carried out to sufficiently high orders. As usual for the dynamically assisted Sauter-Schwinger effect, the additional plane wave induces an exponential enhancement of the pair-creation probability if the combined Keldysh parameter exceeds a certain threshold.