DIAMAGNETIC SUSCEPTIBILITY OF A DONOR IN A GAAS/GA1-XALXAS QUANTUM-WELL HETEROSTRUCTURE AND ITS PRESSURE-DEPENDENCE

The diamagnetic susceptibility (χdin) of a donor in the GaAs quanturn well of the GaAs/Ga1−xAlxAs heterostructure is calculated for a well of infinite strength. The binding energy of the donor electron in different magnetic fields is computed variationally and the χdia values estimated using the Langevin expression. It is found that as the well width increases the χdia values also increase, Using the pressure dependence of the effective mass, dielectric constant, and lattice constant of GaAs, the donor ionization energies are estimated for different pressures of 50 × 108, 150 × 108, and 200 × 108 Pa applied along the growth axis of the superlattice. It is shown that both, the ionization energies and χdia values increase with pressure for a given well width. Also the ionization energy decreases with increasing well width in the presence of both, pressure and magnetic field. Copyright © 1990 WILEY‐VCH Verlag GmbH & Co. KGaA