Carrier dynamics in site-controlled InAs dots analyzed by time-resolved micro-photoluminescence

Formation of dense dots of semiconductor in a sub-micrometer growth site ha s enabled us to analyze strong coupling of quantum dots. Transient microsco pic photoluminescence measurements on site-controlled InAs dots have indica ted the energy transport among laterally coupled dots. The emission spectra as well as the decay time dependence on the emission energy have been inte rpreted by a rate equation model for multiple states. Carriers excited in s maller dots are transported to relatively lower energy levels in larger dot s within the tunneling time and then recombine. (C) 1999 Elsevier Science B .V. All rights reserved.