Tunable electronic transport and unidirectional quantum wires in graphene subjected to electric and magnetic fields

TL;DR

This paper explores how combined electric and magnetic fields can create tunable, unidirectional quantum wires in graphene, enabling controllable electronic states with robust conduction properties.

Contribution

It demonstrates the formation of tunable quantum wires in graphene using electric and magnetic fields, revealing unique unidirectional and surface wave modes.

Findings

Quantum wires support localized electron-hole states controllable by electric fields.

Unidirectional conductivity and robustness to disorder are observed.

Two types of eigenmodes, including coupled surface waves, are identified.

Abstract

Magnetic barriers in graphene are not easily tunable. However, introducing both electric and magnetic fields, provides tunable and far more controllable electronic states in graphene. Here we study such systems. A one-dimensional channel can be formed in graphene using perpendicular electric and magnetic fields. This channel (quantum wire) supports localized electron-hole states, with parameters that can be controlled by an electric field. Such quantum wire offers peculiar conducting properties, like unidirectional conductivity and robustness to disorder. Two separate quantum wires comprise a waveguide with two types of eigenmodes: one type is similar to traditional waveguides, the other type is formed by coupled surface waves propagating along the boundaries of the waveguide.