Controlled tuning of the radiative lifetime in InAs self-assembled quantumdots through vertical ordering

Multilayer structures of InAs quantum dots have been studied by means of ph otoluminescence techniques. A strong increase of the radiative lifetime wit h increasing number of stacked dot layers has been observed at low temperat ures. Moreover, a strong temperature dependence of the radiative lifetime, which is nor present in the single layer samples, has been found in the mul tistacked structures. The observed effects are nicely explained as a conseq uence of the electronic coupling between electrons and holes induced by ver tical ordering. (C) 1999 American Institute of Physics. [S0003-6951(99)0240 4-3].