Nonlinear optical response of wurtzite ZnO from first principles

We present the results of an ab initio theoretical study of the linear and nonlinear optical susceptibilities for the ZnO using pseudo potential plane wave method as implemented in the ABINIT code. We have used the Perdew–Wang exchange-correlation potential based on the local density approximation. The structure properties, the band structure and the density of states are present. The frequency-dependent complex dielectric function ε(ω  ) is calculated. Our calculations show that the edge of the optical absorption for ε2xx(ω) and ε2zz(ω) are located around 3.18 eV. The linear optical properties show a negative uniaxial anisotropy. The scissors correction is used to calculate the optical properties. The optical properties are analyzed in terms of the calculated electronic structure. The imaginary and real parts of the second-order SHG susceptibility were evaluated. It is found that χ333(2)(ω) is the dominant component which shows the largest total Re χijk(2)(0) value 2.63 pm V–1.