Pressure-Dependent Optical and Vibrational Properties of Monolayer Molybdenum Disulfide

Controlling the band gap by tuning the lattice structure through pressure engineering is a relatively new route for tailoring the optoelectronic properties of two dimensional (2D) materials. Here we investigate the electronic and lattice vibrational dynamics of the distorted monolayer 1T-MoS$_{\mathrm{2}}$ (1T') and the monolayer 2H-MoS$_{\mathrm{2}}$ \textit{via} a diamond anvil cell (DAC) and density functional theory (DFT) calculations. The direct optical band gap of the monolayer 2H-MoS$_{\mathrm{2}}$ increases by 11.7{\%} from 1.85 eV to 2.08 eV, which is the highest reported for a 2D transition metal dichalcogenide (TMD) material.