Dimensionality-driven photoproduction of massive Dirac pairs near threshold in gapped graphene monolayers

TL;DR

This paper investigates how gapped graphene monolayers can produce massive Dirac pairs through a nonlinear process involving three-photon absorption, revealing unique threshold behaviors due to the material's two-dimensional structure.

Contribution

It demonstrates a novel nonlinear pair production mechanism in gapped graphene, highlighting differences from QED predictions caused by the material's two-dimensional nature.

Findings

Non-zero pair production rates at the energy threshold.

Threshold behavior differs from QED due to graphene's 2D structure.

Pair production involves nonlinear three-photon absorption.

Abstract

Generation of quasi-particle--hole pairs in gapped graphene monolayers in the combined field of two counterpropagating light waves is studied. The process represents an analogue of electron-positron pair production from the QED vacuum by the Breit-Wheeler effect. We show, however, that the two-dimensional structure of graphene causes some striking differences between both scenarios. In particular, contrary to the QED case, it allows for non-zero pair production rates at the energy threshold when the Breit-Wheeler reaction proceeds nonlinearly with absorption of three photons.