The strong effect of an electric field on the ionization energy of dee
p accepters in asymmetric quantum-well systems is due to the field-dep
endence of the mixing of the states in the heavy- and light-hole subba
nds. The dependence of the ionization energy on the held and the posit
ion of impurities in the structure was calculated in the strongly loca
lized potential model. (C) 1995 American Institute of Physics.