Density Functional Theory Study of Infrared Nonlinear Optical Crystal ZnGeP2

Abstract

The electronic structure and optical properties of ZnGeP2 crystal were studied using DFT. The electronic structure results showed that ZnGeP2 is a nonlinear optical crystal with a direct wide bandgap. The bandgap was calculated to be 1.99 eV using the HSE06 method, which is exactly equal to the experimental value. The optical properties showed strong absorption and reflection in the ultraviolet region and strong transmittance in the infrared region. The average static refractive index of ZnGeP2 was 2.73, and the static birefractive index was 0.04. The above results indicate that ZnGeP2 is a potential infrared nonlinear optical crystal material.