Time-domain quantum interference in graphene

TL;DR

This paper investigates quantum interference effects in graphene under time-dependent electric fields, revealing how electron pair production involves sequences of adiabatic and non-adiabatic transitions, leading to observable interference patterns.

Contribution

It introduces a novel analysis of electron pair production in graphene using strong field QED techniques, highlighting interference phenomena linked to Landau-Zener transitions.

Findings

Pair production occurs via adiabatic and non-adiabatic Landau-Zener transitions.

Interference patterns in momentum space are explained by the adiabatic-impulse model.

Results are relevant for experimental observation of quantum interference in graphene.

Abstract

The electron momentum density obtained from the Schwinger-like mechanism is evaluated for a graphene sample immersed in a homogeneous time-dependent electric field. Based on the analogy between graphene low-energy electrons and quantum electrodynamics (QED), numerical techniques borrowed from strong field QED are employed and compared to approximate analytical approaches. It is demonstrated that for some range of experimentally accessible parameters, the pair production proceeds by sequences of adiabatic evolutions followed by non-adiabatic Landau-Zener transitions, reminiscent of the Kibble-Zurek mechanism describing topological defect density in second order phase transitions. For some field configurations, this yields interference patterns in momentum space which are explained in terms of the adiabatic-impulse model and the Landau-Zener-St\"{u}ckelberg interferometry.