Relaxation mechanisms in self-assembled quantum dots studied by near-field spectroscopy

Summary form only given. The study of carrier relaxation in self-assembled quantum dots (SAQDs) is important for understanding the device physics of zero-dimensional (0D) systems. In previous reports on SAQDs, the photoluminescence (PL) excitation (PLE) resonances do not reflect the higher excited slates observed in PL. This phenomenon has been explained by the multiphonon filtering of excited states. However these discussions are based on the ensemble measurements and more detailed analysis is still needed to determine the real relaxation processes in SAQDs. We have investigated dominant relaxation mechanism in SAQDs by single dot spectroscopy.