Optical absorption and transmission in a molybdenum disulfide monolayer

Abstract

Our recently proposed theoretical formulation [presented in D. Novko et al., Phys. Rev. B 93, 125413 (2016)] is used to study optical absorption and transmission in molybdenum disulfide $({\mathrm{MoS}}_{2})$ monolayer as a function of incident photon energy and angle. The investigation is not focused on exploration of well-documented spin-orbit split excitons around optical absorption onset, but rather on the most intensive features in absorption spectrum in the visible and near-ultraviolet photon energy range $(1.7--4\phantom{\rule{0.28em}{0ex}}\mathrm{eV})$. It is shown that three most intensive peaks, at 2.7, 3.1, and 3.7 eV, result from transitions between $\text{Mo}(d)$ and $\text{S}(p)$ valence and conduction bands and that the character of their charge/current density fluctuations is intrinsically in plane, located in the molybdenum plane. This also implies that ${\mathrm{MoS}}_{2}$ monolayer is completely transparent when illuminated by grazing incidence $p$-polarized light. The validity of the presented results is supported by our effective two-band tight-binding model and finally by good agreement with some recent experimental results.