We propose an effective lattice Hamiltonian for monolayer MoS2 in order to describe the low-energy band structure and investigate the effect of perpendicular electric and magnetic fields on its electronic structure. We derive a tight-binding model based on the hybridization of the d orbitals of molybdenum and p orbitals of sulfur atoms and then introduce a modified two-band continuum model of monolayer MoS2 by exploiting the quasi-degenerate partitioning method. Our theory proves that the low-energy excitations of the system are no longer massive Dirac fermions. It reveals a difference between electron and hole masses and provides trigonal warping effects. Furthermore, we predict a valley degeneracy breaking effect in the Landau levels. Besides, we also show that applying a gate voltage perpendicular to the monolayer modifies the electronic structure including the band gap and effective masses.
@article{arxiv.1302.5901,
title = {Effective lattice Hamiltonian for monolayer MoS2 : Tailoring electronic structure with perpendicular electric and magnetic fields},
author = {Habib Rostami and Ali G. Moghaddam and Reza Asgari},
journal= {arXiv preprint arXiv:1302.5901},
year = {2013}
}