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arXiv · 1304.4831

Tight-binding model and direct-gap/indirect-gap transition in single-layer and multi-layer MoS$_2$

E. Cappelluti·R. Roldán·J. A. Silva-Guillén·P. Ordejón·F. Guinea
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Abstract

In this paper we present a paradigmatic tight-binding model for single-layer as well as for multi-layered semiconducting MoS$_2$ 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.

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E. Cappelluti, R. Roldán, J. A. Silva-Guillén, P. Ordejón, F. Guinea. 2013-04-17. Tight-binding model and direct-gap/indirect-gap transition in single-layer and multi-layer MoS$_2$. https://doi.org/10.1103/physrevb.88.075409

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