Using the DFT to Study the Electronic Structure and Optical Properties for Inse Monolayer

Abstract

The geometric and electrical structural computations can now be used to mimic material surfaces thanks to advancements in computer techniques in recent years. The density functional theory is used in all of these computations. The results of our computations indicate that InSe has an indirect energy gap of 1.53 eV. It can be seen that for the pristine case, the majority and minority density of state (DOS) are fully symmetric. According to the phonon calculations, it has been shown from the results that these monolayers are dynamically stable because they have a positive frequency with a frequency value of 231 cm-1 within the Brillouin region. We take into account the optical characteristics up to 35 eV. Our findings demonstrated that it begins in the visible spectrum. Whereas absorption coefficient peaks located in the UV spectrum. The refractive index begins to increase and then decreases with the increase of photon energy and become a constant value of about 0.9 when the photon energy equals 26 eV. As an internal layer coating between the substrate and the UV-absorbing layer, this monolayer high refractive index makes it possible to employ.