LINEAR-POLARIZATION EFFECTS IN (110) QUANTUM-WELLS FOR LIGHT PROPAGATING PERPENDICULAR TO THE WELL PLANES

The photocurrent spectra of GaAs/Al0.3Ga0.7As quantum wells grown on a (110) substrate were measured at 77 K for linearly polarized light with normal incidence onto the (110) surface. A heavy-hole exciton peak and a light-hole exciton peak were observed in the spectra and each of the two exciton peaks showed an opposite dependence in intensity on the polarization direction: The heavy-hole exciton peak was strengthened for [110BAR] polarization, while the light-hole exciton peak was emphasized for [001] polarization. These linear-polarization effects, which are due to quantum-well effects but are not observed in either (001) or (111) quantum wells, are well explained by the polarization dependence of the optical matrix elements on the basis of an envelope-function approximation.