Ab initio computations of the linear and nonlinear optical properties of stable compounds in AlInN system

The frequency dependent linear and second order nonlinear susceptibilities of AlxIn1−xN have been studied by means of density functional theory within the random phase approximation. Predicted stable AlInN phases from our previous study were investigated. Scissor shift from earlier work was supplemented so as to activate the self-energy effects in response function calculations. By considering the many-body effects, optical calculations of semiconductors are improved. Apart from analyzing the real and imaginary optical spectra, calculations of refractive index were also carried out. Both low energy limit of real part and refractive index are increasing monotonically with a decrease in Al composition. Analyses of intraband and interband contributions towards nonlinear χ3332(2ω, ω, ω) are too discussed. Our calculations show that |χ3332(0)| values for the stable alloys range from 0.18 to 120.98 pm/V.