Modeling the optical dielectric function of GaAs and AlAs: Extension of Adachi’s model

Optical dielectric function model of Ozaki and Adachi [J. Appl. Phys. 78, 3380 (1995)] is augmented by introducing Gaussian-like broadening function instead of Lorentzian broadening. In this way a consistent and comparatively simple analytic formula has been obtained, which accurately describes the optical dielectric function of GaAs and AlAs in a wide spectral range between 0.1 and 6 eV. The acceptance-probability-controlled simulated annealing technique was used to fit the model to experimental data.