Electronic bandstructure of disordered superlattices

The disordering of semiconductor superlattices is analysed in the spatial Fourier domain. It is demonstrated that disordering is equivalent to suppressing the higher-order Fourier coefficients of the alloy profile. Two superlattice bandstructure algorithms are developed in the Fourier domain which allow the electronic envelope function and energy to be determined. The first employs the effective mass approximation. The second is a 14-band k . p which includes nonparabolicity, anisotropy and noncentrosymmetry which are particularly relevant in the determination of nonlinear optical coefficients. (C) 1999 Academic Press.