Study of photoluminescence inCu2O

Abstract

We have studied the photoluminescence spectrum of ${\mathrm{Cu}}_2$O using a tunable dye laser. We found that most of the luminescence peaks can be identified as due to recombination of the $1 s$ yellow exciton of ${\mathrm{Cu}}_2$O or its phonon replica. These phonon replicas showed asymmetric broadening with increase in temperature. A few of the lines showed very strong temperature dependence disappearing rapidly at high temperature. The origins of these lines are still a matter of speculation. The luminescence excitation spectrum of ${\mathrm{Cu}}_2$O is also presented and interpreted.