Light Emission by Monolayers of Molybdenum Disulfide

Abstract

A comprehensive study of molybdenum disulfide monolayers formed on a silicon substrate is carried out using Raman scattering (RS), photoluminescence (PL), and by comparison with the data of atomic force microscopy (AFM). Maps of the intensity distribution of exciton PL and Raman scattering by optical phonons from monolayer MoS $${}_{2}$$ films are obtained. The dependences of the frequencies of the fundamental vibrational modes of MoS $${}_{2}$$ (A $${}_{\textrm{1g}}$$ and E $${}_{\textrm{2g}}$$ ) on the thickness of monolayer coatings are obtained. An enhancement of the Raman mode of the optical phonon of silicon by a bilayer of molybdenum disulfide is found. A hypothesis on the interference enhancement of Raman scattering of light by phonon modes of silicon is proposed.