Driven quantum tunneling and pair creation with graphene Landau levels

TL;DR

This paper models how strong magnetic and laser fields in graphene can induce electron-hole pair creation, drawing parallels with quantum electrodynamics, and explores how pulse duration influences pair yield.

Contribution

It introduces a numerical approach to simulate driven tunneling in graphene Landau levels, linking it to QED pair creation, and analyzes the effects of pulse duration and field strength.

Findings

Pulse duration controls maximum pair yield.

Pair yields are significant at achievable magnetic fields and laser intensities.

The study provides a framework for experimental exploration of QED phenomena in graphene.

Abstract

Driven tunneling between graphene Landau levels is theoretically linked to the process of pair creation from vacuum, a prediction of quantum electrodynamics (QED). Landau levels are created by the presence of a strong, constant, quantizing magnetic field perpendicular to a graphene mono-layer. Following the formal analogy between QED and the description of low-energy excitations in graphene, solutions of the fully interacting Dirac equation are used to compute electron-hole pair creation driven by a circularly or linearly polarized field. This is achieved via the coupled channel method, a numerical scheme for the solution of the time-dependent Dirac equation in the presence of bound states. The case of a monochromatic driving field is first considered, followed by the more realistic case of a pulsed excitation. We show that the pulse duration yields an experimental control parameter over the maximal pair yield. Orders of magnitude of the pair yield are given for experimentally achievable magnetic fields and laser intensities weak enough to preserve the Landau level structure.