Twist-controlled Resonant Tunnelling between Monolayer and Bilayer Graphene

TL;DR

This study explores how twist angle and gate voltages in a graphene heterostructure influence tunnelling current, revealing controllable electronic properties for potential device applications.

Contribution

It introduces a detailed electrostatic model of a graphene-based tunnelling transistor with twist control, highlighting the tunability of its I-V characteristics.

Findings

Gate voltages allow precise control of tunnelling behavior.

Twist angle significantly affects the device's electronic response.

The model maps I-V characteristics in the low energy regime.

Abstract

We investigate the current-voltage characteristics of a field-effect tunnelling transistor comprised of both monolayer and bilayer graphene with well-aligned crystallographic axes, separated by three layers of hexagonal boron nitride. Using a self-consistent description of the device's electrostatic configuration we relate the current to three distinct tunable voltages across the system and hence produce a two-dimensional map of the I-V characteristics in the low energy regime. We show that the use of gates either side of the heterostructure offers a fine degree of control over the device's rich array of characteristics, as does varying the twist between the graphene electrodes.