First-overtone response in modulated photoluminescence emission in silicon at room temperature

Abstract

At sufficient photoexcitation, radiative relaxation of excess carriers in semiconductors becomes quadratically dependent on the excess carrier density and can lead to photoluminescence emission at the first overtone of the modulation frequency of the incident light. We have observed, for the first time, a first-overtone component in amplitude-modulated photoluminescence in silicon at room temperature and describe its origin.