Photoluminescence of GaN/AlN quantum dots at high excitation powers

Abstract

Excitation power and temperature dependencies of the photoluminescence (PL) of wurtzite GaN/AlN quantum dots (QDs) grown by molecular beam epitaxy have been investigated. The PL band of the QDs exhibited a shift to lower energy with increasing excitation power. This red shift was attributed to the band-gap renormalization. The non-stationary PL decay law is non-exponential and varies over the spectrum. The PL band of the GaN/AlN QDs shifts to lower energy with delay time after a pulsed excitation as a result of the increase of the carrier lifetime with increase in the QD size. © 2010 Wiley-VCH Verlag GmbH & Co. KGaA.