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

摘要

Formation of dense dots of semiconductor in a sub-micrometer growth site has enabled us to analyze strong coupling of quantum dots. Transient microscopic photoluminescence measurements on site-controlled InAs dots have indicated the energy transport among laterally coupled dots. The emission spectra as well as the decay time dependence on the emission energy have been interpreted by a rate equation model for multiple states. Carriers excited in smaller dots are transported to relatively lower energy levels in larger dots within the tunneling time and then recombine.