Quasiparticle band structure calculation of monolayer, bilayer, and bulk MoS<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msub><mml:mrow/><mml:mn>2</mml:mn></mml:msub></mml:math>

Abstract

Quasiparticle self-consistent $GW$ calculations of the band structures and related effective-mass parameters are carried out for bulk, monolayer, and bilayer MoS${}_{2}$. Including excitonic effects within the Mott-Wannier theory, quantitative agreement is obtained between the $A$, $B$ excitons, measured by absorption [Phys. Rev. Lett. 105, 136805 (2010)], and the calculated exciton gap energies at $K$. The $A$-$B$ splitting arises from the valence-band splitting which in the monolayer is entirely due to spin-orbit coupling and leads to spin-split states, while in the bilayer it is a combined effect of interlayer and spin-orbit coupling.