Multi-pair states in electron-positron pair creation

TL;DR

This paper develops a quantum field theoretical and numerical framework to analyze multi-pair electron-positron creation in ultra-strong electromagnetic fields, revealing detailed multi-particle dynamics, spin effects, and momentum distributions.

Contribution

It introduces a novel quantum field theoretical approach combined with numerical methods to study multi-pair electron-positron creation, including multi-pair statistics and spin effects, in regimes between nonperturbative and perturbative regimes.

Findings

Multi-pair states are significant in intermediate regimes of pair creation.

Spin and helicity are influenced by laser polarization.

The approach provides detailed multi-particle and momentum distribution insights.

Abstract

Ultra strong electromagnetic fields can lead to spontaneous creation of single or multiple electron-positron pairs. A quantum field theoretical treatment of the pair creation process combined with numerical methods provides a description of the fermionic quantum field state, from which all observables of the multiple electron-positron pairs can be inferred. This allows to study the complex multi-particle dynamics of electron-positron pair creation in-depth, including multi-pair statistics as well as momentum distributions and spin. To illustrate the potential benefit of this approach, it is applied to the intermediate regime of pair creation between nonperturbative Schwinger pair creation and perturbative multiphoton pair creation where the creation of multi-pair states becomes nonnegligible but cascades do not yet set in. Furthermore, it is demonstrated how spin and helicity of the created electrons and positrons are affected by the polarization of the counterpropagating laser fields, which induce the creation of electron-positron pairs.