Photoluminescence of Amorphous 2${\mathrm{As}}_2$${\mathrm{Te}}_3$ · ${\mathrm{As}}_2$${\mathrm{Se}}_3$ Films

The photoluminescence of amorphous 2${\mathrm{As}}_2$ ${\mathrm{Te}}_3$·${\mathrm{As}}_2$ ${\mathrm{Se}}_3$ films has been measured from 2 to 150°K with niobium-doped yttrium aluminum garnet laser excitation. The external quantum efficiency is estimated to be 20%. A typical spectrum consists of a broad band peaked at 0.61 eV with a half-width of 0.15 eV. The energy value for the luminescence peak supports the concept of a recombination gap in amorphous semiconductors.