Effects of strain on the electronic and optical properties of MgO (111) nanosheet

Abstract

High optical transparency, thermal and thermodynamic stabilities, low dielectric constant and refractive index of MgO are promising for different applications of this material. In this work the electronic and optical properties of MgO (111) nanosheet under compressive and tensile strain were investigated by density functional theory (DFT). The results showed that the band gap of MgO nanosheet decreased from 3.45 to 2.16 eV when tensile strain of s = 15% was applied on the lattice parameter of MgO and increased to 4.05 eV by means of compressive strain of s=-15%. The optical parameters such as real and imaginary part of dielectric function, reflectivity, refraction, extinction coefficient and energy loss and their alterations under applied strain were studied. Position of plasmon peak was changed in linear pattern as a function of applied strain from s=−15% to 15%.