Miniband Structure Formation of p-type delta-doped Superlattices in GaAs

Abstract

We present the electronic structure of flnite p-type delta-doped superlattices in GaAs. We use the flrst neighbors sp 3 s ⁄ tight-binding approximation including spin for the miniband structure analysis. The calculation is based on analytical expression for the Hartree potential of the inhomogeneous part, previously obtained within the Thomas-Fermi (TF) ap- proximation. This potential is considered as an external potential in the computations, so, it is added to the diagonal terms of the tight-binding Hamiltonian. We give a detail description of the delta-doped superlattices, this is, we study the miniband formation as a function of the impurity density (n2D) and the superlattice period (d), obtaining the regions of superlattice, multiple well and isolate well behavior. We also compare our results with the theoretical and experimental data available, obtaining a reasonable agreement.