Screening effects in piezoelectric strained [111]-grown (In, Ga)As/(Al, Ga)As quantum wells.

The optical nonlinearities produced by screening of the piezoelectric field by photogenerated carriers in a [111]-grown (In,Ga)As/(Al,Ga)As single strained-layer quantum well structure are calculated and compared with those in a [001]-grown structure. Nonlinear absorption and refractive index spectra show that screening of the strain-induced electric field by photo-carriers that have escaped from the [111]-grown quantum well produces optical nonlinearities comparable to those in the more conventional [001]-grown quantum well.