Electronic eigenstates and inter-sub-band transitions in doped heterostructure superlattices

The authors calculate the self-consistent potential and electronic eigenstates of doped heterostructure superlattices. The minibanding effects, nonparabolicity of the conduction band and exchange-correlation effects are included. They calculate the transition energy shifted by many body effects and the dipole matrix element of the inter-sub-band excitations. The miniband energies of the excited states calculated as a function of the quantum well width or of spacer width show a level crossing. Thereby they can explain the dependence on quantum well width of sub-band resonance experiments using narrow quantum wells. Numerical results are given for the InGaAs/InP system. They find quantitative agreement with recently measured transition energies.