Generation of valley polarized current in bilayer graphene

TL;DR

This paper proposes a device using bilayer graphene and terahertz light to generate valley polarized currents by inducing valley-specific dynamical states, enabling valley filtering.

Contribution

It introduces a novel method to produce valley polarized currents in bilayer graphene through dynamical states induced by terahertz light and electric fields.

Findings

Dynamical states are induced in the gapped energy region.

Proper tuning of system parameters yields valley-specific states.

Valley polarized states can filter arbitrary electron currents.

Abstract

We propose a device for the generation of valley polarized electronic current in bilayer graphene. By analyzing the response of this material to intense terahertz frequency light in the presence of a transverse electric field, we demonstrate that dynamical states are induced in the gapped energy region, and if the system parameters are properly tuned, these states exist only in one valley. The valley polarized states can then be used to filter an arbitrary electron current, so generating a valley polarized current.