Optical properties and quasiparticle energies in the two-layered hydrogenated gallium nitrate nanosheet: A DFT study

• Published in: Computational and theoretical chemistry 2019-03, Vol.1151, p.31-35
• Main Authors: Faghihzadeh, Somayeh, Shahtahmasebi, Nasser, Vahedi Fakhrabad, Davoud
• Format: Article
• Language: English
• Subjects: Dielectric function; GW approximation; Optical properties; Self-energy
• ISSN: 2210-271X
• DOI: 10.1016/j.comptc.2019.01.025

The electronic structure and optical properties of the hydrogenated two-layered GaN based on first principle many body Green’s function and Bethe Salpeter equation formalism are investigated. [Display omitted] •The optical properties of H-GaN-H are studied using GW and BSE formalism.•The first absorption peak locates at 3 eV, which is optically a bright exciton.•The binding energy of the first exciton is 1.1 eV.•The obtained band gap of H-GaN-H is 4.1 eV using quasiparticle corrections. In this work, the electronic structure and optical properties of two-layered hydrogenated GaN were investigated. The results were obtained via first principle calculations based on density functional theory (DFT) using GW approximation and two particle Bethe–Salpeter equation along with electron-hole effect. The results show that direct band gap of the sample change from 1.67 eV to, 4.1 eV considering electron-electron effects. Based on our findings, the first peak obtained from the imaginary part of the dielectric function for the direction parallel to the nanosheet plane observed in 3 eV, the energy corresponding to the first bound exciton state was obtained as 1.1 eV. The first absorption peak was observed in two parallel and perpendicular directions to the plane being invisible region.