One-way transport in laser-illuminated bilayer graphene: A Floquet isolator

TL;DR

This paper demonstrates a method to induce one-way charge and valley transport in bilayer graphene using laser illumination and bias voltage, creating a Floquet bandstructure that functions as an electronic isolator.

Contribution

It introduces a novel mechanism for non-reciprocal transport in bilayer graphene via Floquet engineering, distinct from quantum pumping.

Findings

Achieved one-way transport through Floquet bandstructure manipulation.

Demonstrated hybridization of edge states enabling isolator behavior.

Proposed a new device concept for unidirectional electronic transport.

Abstract

We explore the Floquet band-structure and electronic transport in laser-illuminated bilayer graphene. By using a bias voltage perpendicular to the graphene bilayer we show how to get one-way charge and valley transport among two unbiased leads. In contrast to quantum pumping, our proposal uses a different mechanism based on generating a non-reciprocal bandstructure with a built-in directionality. The Floquet states at one edge of a graphene layer become hybridized with the continuum on the other layer, and so the resulting bandstructure allows for one-way transport as in an \textit{isolator}. Our proof-of-concept may serve as a building block for devices exploiting one-way states.