Directional photoelectric current across the bilayer graphene junction

TL;DR

This paper explores how an external electromagnetic field can control directional photoelectric current in bilayer graphene, enabling switchable transparency for potential use in infrared optical devices.

Contribution

It introduces a novel mechanism for controlling chiral tunneling in bilayer graphene using electromagnetic fields, demonstrating a switch from zero to perfect transparency.

Findings

Electromagnetic field modulates tunneling transparency in bilayer graphene.

The phase correlation between electrons and holes is affected by the external field.

Potential applications in sub-millimeter and far-infrared optical devices.

Abstract

A directional photon-assisted resonant chiral tunneling through a bilayer graphene barrier is considered. An external electromagnetic field applied to the barrier switches the transparency $T$ in the longitudinal direction from its steady state value T=0 to the ideal T=1 at no energy costs. The switch happens because the a.c. field affects the phase correlation between the electrons and holes inside the graphene barrier changing the whole angular dependence of the chiral tunneling (directional photoelectric effect). The suggested phenomena can be implemented in relevant experiments and in various sub-millimeter and far-infrared optical electronic devices.