Electronic transport in disordered MoS$_2$ nanoribbons

TL;DR

This study investigates the electronic structure and transport properties of MoS₂ nanoribbons, revealing edge state localization and their sensitivity to different types of disorder, with implications for nanoscale electronic devices.

Contribution

It provides a detailed analysis of edge states in MoS₂ nanoribbons and their robustness against various disorder types, using an accurate tight-binding model and Green's function techniques.

Findings

Edge states can be localized at a single edge independent of width.

Short-range disorder suppresses conductance of edge states.

Long-range disorder has minimal impact on transport within the bulk gap.

Abstract

We study the electronic structure and transport properties of zigzag and armchair monolayer molybdenum disulfide nanoribbons using an 11-band tight-binding model that accurately reproduces the material's bulk band structure near the band gap. We study the electronic properties of pristine zigzag and armchair nanoribbons, paying particular attention to the edges states that appear within the MoS$_2$ bulk gap. By analyzing both their orbital composition and their local density of states, we find that in zigzag-terminated nanoribbons these states can be localized at a single edge for certain energies independent of the nanoribbon width. We also study the effects of disorder in these systems using the recursive Green's function technique. We show that for the zigzag nanoribbons, the conductance due to the edge states is strongly suppressed by short-range disorder such as vacancies. In contrast, the local density of states still shows edge localization. We also show that long-range disorder has a small effect on the transport properties of nanoribbons within the bulk gap energy window.