Ab initio based atomic scattering amplitudes and {002} electron structure factors of In_xGa_1−xAs/GaAs quantum wells

The atomic scattering amplitudes of the various atoms of the systems Ga_1−xIn_xAs, GaAs_1−xN_x and InAs_1−xN_x are calculated using the density functional theory (DFT) approach. The scattering amplitudes of N, Ga, As and In in the model systems are compared with the frequently used Doyle and Turner values. Deviation from the latter values is found for small scattering vectors (s<0.3Å⁻¹) and for these scattering vectors dependence on the orientation of the scattering vector and the chemical environment is reported. We suggest a parametrization of these modified scattering amplitudes (MASAs) for small scattering vectors (s<1.0Å⁻¹). The MASAs are exploited within zero pressure classical Metropolis Monte Carlo (MC), finite temperature calculations to investigate the effect of quantum well size on the electron {002} structure factor (SF) of Ga_1−xIn_xAs quantum wells.