Shallow Donor Binding Energies in Semiconductors in a Magnetic Field

Abstract

AbstractThe binding energies of the P donor in Si and the Si and S donors in GaP at the cation and anion sites, respectively, in strong magnetic fields are calculated using a variational procedure. The central cell effects are taken into account using an Yukawa type potential and its effects on the ionization energies are obtained for various magnetic fields. In GaP the electron—lattice coupling (polaronic effect) is also taken into account both, in fixing the parameters of the model potential and also in the computation of binding energies. It is shown that the central cell effects are important especially for magnetic fields of the order of γ ≈︁ 100. The contribution from the electron—lattice coupling is small and seen to decrease with the increase of magnetic field in confirmation with previous works. The central cell effect enhances the electron—lattice coupling appreciably, the enhancement being 30 to 100% for the range of magnetic fields investigated.