In this paper we present a paradigmatic tight-binding model for single-layer as well as for multi-layered semiconducting MoS2 and similar transition metal dichalcogenides. We show that the electronic properties of multilayer systems can be reproduced in terms of a tight-binding modelling of the single-layer hopping terms by simply adding the proper interlayer hoppings ruled by the chalcogenide atoms. We show that such tight-binding model permits to understand and control in a natural way the transition between a direct-gap band structure, in single-layer systems, to an indirect gap in multilayer compounds in terms of a momentum/orbital selective interlayer splitting of the relevant valence and conduction bands. The model represents also a suitable playground to investigate in an analytical way strain and finite-size effects.
@article{arxiv.1304.4831,
title = {Tight-binding model and direct-gap/indirect-gap transition in single-layer and multi-layer MoS$_2$},
author = {E. Cappelluti and R. Roldán and J. A. Silva-Guillén and P. Ordejón and F. Guinea},
journal= {arXiv preprint arXiv:1304.4831},
year = {2013}
}