Time-resolved photoluminescence studies of GaN epilayers grown by gas source molecular beam epitaxy on an AlN buffer layer on (111) Si

Abstract

Optical properties of GaN epilayers grown by gas source molecular beam epitaxy on a (111) Si substrate with an AlN buffer layer are described. The mechanism of energy transfer between different excitonic emissions is proposed based on the results of time-resolved photoluminescence (PL) and PL kinetics measurements. It is suggested that tunneling of excitons between bound and free excitons is responsible for the observed PL decay transients and their temperature dependence.