Photoluminescence linewidths of piezoelectric quantum wells

The photoluminescence linewidths of strained InxGa1-xAs/GaAs quantum wells grown on (111)B GaAs substrates are shown to differ radically from those gr own on (001) substrates. In (111)B structures, the linewidth in wide wells is broadened significantly compared with (001) structures. This broadening cannot be explained by well width or alloy fluctuations alone, and suggests the presence of another mechanism which we believe is due to the piezoelec tric field and its sensitivity to screening under illumination. (C) 1999 Am erican Institute of Physics. [S0003-6951(99)05539-4].