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arXiv · 1306.1666

Plasmons and screening in a monolayer of MoS$_2$

Andreas Scholz·Tobias Stauber·John Schliemann
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Abstract

We investigate the dynamical dielectric function of a monolayer of molybdenum disulfide within the random phase approximation. While in graphene damping of plasmons is caused by interband transitions, due to the large direct band gap in monolayer MoS$_2$ collective charge excitations enter the intraband electron hole continuum similar to the situation in two-dimensional electron and hole gases. Since there is no electron-hole symmetry in MoS$_2$, the plasmon energies in p- and n-doped samples clearly differ. The breaking of spin degeneracy caused by the large intrinsic spin-orbit interaction leads to a beating of Friedel oscillations for sufficiently large carrier concentrations, for holes as well as for electrons.

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Andreas Scholz, Tobias Stauber, John Schliemann. 2013-06-07. Plasmons and screening in a monolayer of MoS$_2$. https://doi.org/10.1103/physrevb.88.035135

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