SCREENING EFFECT ON POLARIZABILITIES OF SHALLOW DONORS AND ACCEPTORS IN FINITE-BARRIER QUANTUM-WELLS

Polarizabilities of shallow donors and accepters in finite-barrier GaA s/Ga1-xAlxAs quantum wells are calculated using Hasse's variational me thod within the effective mass approximation. The effect of spatially dependent screening on polarizabilities is taken into account with an r-dependent dielectric response. It is shown that spatially dependent screening effects can be more important for accepters than for donors in GaAs/Ga(1-x)A(x)As quantum wells. The effects of electric and magne tic fields on binding energy are also studied.