Valley filter in strain engineered graphene

TL;DR

This paper introduces a device in strain-engineered graphene that efficiently produces valley-polarized current by combining uniaxial strain and magnetic barriers, enabling perfect valley filtering under accessible conditions.

Contribution

It presents a novel device design that achieves perfect valley filtering in graphene using strain and magnetic barriers, a significant advancement over previous methods.

Findings

Perfect valley filtering is achievable with proper tuning of strain, magnetic field, and Fermi level.

The device is simple, robust, and compatible with experimental conditions.

High efficiency in producing valley-polarized current is demonstrated.

Abstract

We propose a simple, yet highly efficient and robust device for producing valley polarized current in graphene. The device comprises of two distinct components; a region of uniform uniaxial strain, adjacent to an out-of-plane magnetic barrier configuration formed by patterned ferromagnetic gates. We show that when the amount of strain, magnetic field strength, and Fermi level are properly tuned, the output current can be made to consist of only a single valley contribution. Perfect valley filtering is achievable within experimentally accessible parameters.