Edge states in dichalcogenide nanoribbons and triangular quantum dots

TL;DR

This paper investigates edge states in monolayer MoS₂ nanoribbons and quantum dots, revealing localized states in the band gap influenced by band curvature and topological properties.

Contribution

It introduces an effective two-band model to analyze edge states in MoS₂ nanostructures, linking their existence to topological characteristics.

Findings

Edge states are localized on the borders of nanoribbons and quantum dots.

The presence of edge states depends on the band curvature.

Edge states are related to the topological properties of the Hamiltonian.

Abstract

The electronic structure of monolayer MoS$_2$ nanoribbons and quantum dots have been investigated by means of an effective $\mathbf{k}\cdot \mathbf{p}$ two-band model. Both systems with borders exhibit states spatially localized on the edges and with energies lying in the band gap. We show that the conduction and valence band curvatures determine the presence/absence of these states whose origin has been related to the marginal topological properties of the MoS$_2$ single-valley Hamiltonian.