OPTICAL AND LUMINESCENCE PROPERTIES OF DISORDERED SUPERLATTICES

A new semiconductor has been proposed which is characterized by showing both the amorphous-like and the single-crystal-like properties. The semiconductor exhibits unusual luminescent capability caused by artificial disordering along one direction, while epitaxial growth is possible on the surface perpendicular to the disordered direction. Experimental results on photoluminescence intensities, their temperature dependence, optical absorption, and time-resolved photoluminescence decay time of the disordered superlattices are presented and compared with those of a bulk alloy and an ordered superlattice. The unusual luminescence capability has been interpreted in terms of the Lifshitz localization and the relaxation of the momentum conservation.