Quantum decoherence of excited states in self assembled quantum dots

Summary form only given. Semiconductor quantum dots (QDs) provide excellent ground to explore many fundamental physical phenomena. One of such phenomena is quantum coherence/decoherence of confined carriers which is critical for quantum information processing and other applications. Recently, such phenomena have been studied experimentally as well as theoretically in naturally formed quantum dot systems. On the other hand, for technologically more important self assembled quantum dots (SAQDs), various experimental and theoretical investigations indicate a much richer electronic structure and more complex inter-level energy relaxation mechanisms. We report on the investigation of photoluminescence spectra and dephasing times (T/sub 2/) of various excited sates of hundreds of individual In/sub 0.5/Ga/sub 0.5/As SAQDs grown by molecular beam epitaxy.