Unipolar transport in bilayer graphene controlled by multiple p-n interfaces

TL;DR

This paper demonstrates unipolar transport in bilayer graphene using multiple p-n junctions controlled by electrostatic biasing, showing enhanced current suppression and saturation effects with increasing junctions.

Contribution

It introduces a method to control unipolar transport in bilayer graphene via multiple p-n interfaces with electrostatic gating, highlighting the effects of junction number on device performance.

Findings

Current suppression increases with more p-n junctions.

Saturation of drain current occurs at high source-drain voltages.

OFF state is achieved by multiple barriers in p-n junctions.

Abstract

Unipolar transport is demonstrated in a bilayer graphene with a series of p-n junctions and is controlled by electrostatic biasing by a comb-shaped top gate. The OFF state is induced by multiple barriers in the p-n junctions, where the band gap is generated by applying a perpendicular electric field to the bilayer graphene, and the ON state is induced by the p-p or n-n configurations of the junctions. As the number of the junction increases, current suppression in the OFF state is pronounced. The multiple p-n junctions also realize the saturation of the drain current under relatively high source-drain voltages.