Thomas–Fermi–Dirac calculations of valence band states in two p‐type delta‐doped ZnSe quantum wells

Abstract

PACS 73.21.Fg, 73.61.Ga We present the hole sub-band structure study in two p-type δ -doped ZnSe QW's. An analytical expression for the Hartree-Fock potential is obtained following the lines of the Thomas-Fermi-Dirac (TFD) approximation. We have analyzed the dependence of the hole energy levels to the impurity density and the interlayer distance between wells. The exchange effects are also included in the present survey. We find that many body effects cannot be ignored because these are really important in the calculation at least in the low concentration regime. We have obtained an energy difference between the top of the valence band and the ground energy of the heavy hole ladder of 0 29 0in good agreement with the experimental reports ( DAP 2 792 E = . eV) available. We calculate the mobility ratio between double δ -doped QW's and simple δ -doped QW based on a phenomenological formula. We find the optimum interlayer distance between wells for maximum mobility for three impurity concentrations, which can be of great importance for technological applications.

Subband and transport calculations in double n-type δ-doped quantum wells in Si

“…It is worth mentioning that the former phenomenological formulas have been applied successfully to p-type ␦-doped systems. 40,46…”

“…[33][34][35][36][37][38][39][40][41][42][43][44][45][46] These studies have been performed in GaAs, [33][34][35][36][37][38][39][40][41] Si, 42-45 and ZnSe. 46 In n-type double ␦-doped quantum wells in Si there are two representative works. 42,44 The electrical transport between locally grown ␦-doped layers spaced 63-146 nm has been investigated.…”

“…In this work we present the results obtained for the electronic levels and the relative mobility as a function of the doping density and the distance between ␦ wells by means of the Thomas-Fermi ͑TF͒ approximation and a phenomenological formula for the mobility previously proposed and applied to p-type ␦-doped systems. 40,45,46 We also paid attention to the exchange-correlation effects, comparing the Hartree and Hartree-Fock calculations.…”