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We present the hole subband structure of two coupled p-type δ-doped GaAs quantum wells as a function of the impurity concentration and the distance l between them, including exchange effects. We present an analytical expression for the Hartree–Fock potential as a function of these two magnitudes, by using the Thomas–Fermi–Dirac approximation. The numerical results for a double Be-δ-doped GaAs quantum well show that many body effects are important when the concentration is low and the energy levels are degenerate for l⩾100 A˚ and an impurity concentration of 5 × 1012 cm−2, while without exchange effects the energy levels are degenerated for l⩾150 A˚ and the same impurity concentration. We present an expression for the relative electronic mobility, that is, we calculate the ratio of the electronic mobility of a double δ-doped quantum well and that of a simple δ-doped quantum well. The theoretical results agree quite well with the experimental data available. [Copyright &y& Elsevier]

We study the electronic band structure of the zinc-blende phase (0 0 1) ideal surface of GaN, AlN and BN by means of an empirical tight binding sp3 s* Hamiltonian with nearest-neighbour interactions plus some second-neighbour interactions and the surface Green function matching method. We have studied both anion and cation terminated surfaces and we have obtained the different surface states with their corresponding spectral localization and orbital character. [Copyright &y& Elsevier]

We present an alternative and efficient way for calculating the superlattice Green function for discrete systems. The idea is to consider the superlattices as a crystal with the unit cell having the size of the superlattice period in the growth direction. The calculation method takes into account the matrix structure of the system Hamiltonian and a block tridiagonal matrix inversion algorithm. To illustrate the method we study the electronic band structure of a semiconductor superlattice described by means of an empirical sp3s* tight-binding Hamiltonian, including nearest-neighbor interactions and spin–orbit coupling. [Copyright &y& Elsevier]