Doping screening of polarization fields in nitride heterostructures

Using self-consistent tight-binding calculations, we show that modulation doping can be used to screen macroscopic polarization fields in nitride quantum wells. The blue-shift of photoluminescence peak as well as the reduction of radiative recombination lifetime at increasing doping density is explained and correlated to polarization-field screening. The field-induced ionization of the dopants and its relation with alloy composition in the heterostructure barriers is also analyzed. (C) 2000 American Institute of Physics. [S0003-6951(00)05026-9].