Strain effect on the electronic and optical properties of anisotropic Au2Te monolayer

Abstract

In this article, the strain effect on the electronic and optical properties of Au2Te monolayer is investigated based on first-principles calculations. The band gap responds monotonically to uniaxial strain, and it increases (decreases) from 1.13 (1.51) eV to 1.45 (1.13) eV for applying strain along the x (y) direction from -5% to +5%. The band gap varies in a parabolic trend for the applied biaxial strain, and both compressive and stretch strains increase the band gap. The indirect bandgap characteristic of Au2Te monolayer is maintained under both uniaxial and biaxial strains. In addition, the light absorption edge blueshift (redshift) with the increasing (decreasing) strain-induced band gap. Notably, the optical response is more sensitive to biaxial strain than uniaxial strain. These tunable properties endow the anisotropic Au2Te monolayer as a promising 2D semiconductor for anisotropic optoelectronic devices.