Electronic structures and optical properties of SnSe_(2(1-x))O_(2x) alloys

摘要

Based on density functional theory, the electronic structures and optical properties of SnSe_(2(1-x))O_(2x) alloys are investigated for the first time. Numerical results show that when oxygen concentration x increases(x ≤ 0.125), the band gap values of SnSe_(2(1-x))O_(2x) alloys can be decreased from 1.03 to 0.77 eV, and the gap states are absent. The dielectric functions and optical absorptions are anisotropic in the SnSe_(2(1-x))O_(2x) alloys. Moreover, the oxygen substitution of selenium affects obviously the optical properties along the x-y plane in the SnSe_(2(1-x))O_(2x) alloys. These results are interesting and indicate that the SnSe_(2(1-x))O_(2x) alloys with tunable band gap may serve as a promising candidate for near-infrared optical applications.