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تسجيل مستخدم جديدProbing exciton localization in non-polar GaN/AlN Quantum Dots by single dot optical spectroscopy
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We present an optical spectroscopy study of non-polar GaN/AlN quantum dots by time-resolved photoluminescence and by microphotoluminescence. Isolated quantum dots exhibit sharp emission lines, with linewidths in the 0.5-2 meV range due to spectral diffusion. Such linewidths are narrow enough to probe the inelastic coupling of acoustic phonons to confined carriers as a function of temperature. This study indicates that the carriers are laterally localized on a scale that is much smaller than the quantum dot size. This conclusion is further confirmed by the analysis of the decay time of the luminescence.
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Sergio De Rinaldis (NNL-National Nanotechnology Laboratory of INFM
, n ISUFI-Istituto Superiore Universitario per la Formazione Interdisciplinare
, n University of Lecce
2002
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