Strain effects of stability, transport, and electro-optical properties of novel Ga2TeS monolayer

Here, we construct a novel Ga2TeS monolayer with the diamondene-like structure. Based on DFT + G0W0 + BSE calculations, we deeply explore the monolayer (stability, transport, and electro-optical properties) and biaxial strain effects. The Ga2TeS monolayer shows dynamical and thermal stabilities, a high electron mobility (larger than 2000 cm2∙V−1∙s−1), a moderate direct bandgap, and a superior light absorption in a broad region, respectively. More interestingly, its optical spectrum is ruled by the excitons, in which the exciton binding energy can gain a desirable value. Under the applied biaxial strains, a tunable bandgap, an improved electron mobility, and a significant enhancement for the visible-light absorption are observed in the Ga2TeS monolayer. These results suggest the Ga2TeS monolayer can be considered as a potential optoelectronic material.