Electronic properties and transport in metal/2D material/metal vertical junctions

TL;DR

This study uses computational methods to analyze how stacking and thickness affect the electronic and transport properties of metal/2D material/metal heterostructures, providing insights for device optimization.

Contribution

It offers a detailed simulation-based analysis of electronic properties in metal/2D material/metal junctions, emphasizing the effects of stacking configurations and layer thickness.

Findings

Orbital hybridization significantly alters electronic states in monolayers.

Interlayer coupling preserves the intrinsic properties of the middle layer.

Designing multilayer structures can optimize electronic device performance.

Abstract

We simulate the electronic and transport properties of metal/two-dimensional material/metal vertical heterostructures, with a focus on graphene, hexagonal boron nitride and two phases of molybdenum diselenide. Using density functional theory and non-equilibrium Green's function, we assess how stacking configurations and material thickness impact important properties, such as density of states, potential barriers and conductivity. For monolayers, strong orbital hybridization with the metallic electrodes significantly alters the electronic characteristics, with the formation of states within the gap of the semiconducting 2D materials. Trilayers reveal the critical role of interlayer coupling, where the middle layer retains its intrinsic properties, thus influencing the overall conductivity. Our findings highlight the potential for customized multilayer designs to optimize electronic device performance based on two-dimensional materials.