Energy relaxation of InN thin films

Abstract

The energy relaxation of InN thin films has been studied by ultrafast time-resolved photoluminescence technique. The obtained carrier cooling curves can be explained by carriers releasing excessive energy through the carrier–LO-phonon interaction. The extracted effective phonon emission times decrease as the photoexcited carrier concentration reduces and come close to the theoretical prediction of 23fs at small carrier concentration. The reduction of energy loss rate at high photoexcited carrier density is attributed to the hot phonon effect.