Degenerate Pump–Probe Photoluminescence Study on Quantum Dots Operating in Linear Recombination Regime

The carrier lifetime of self-assembled quantum dots (QDs) is investigated by a time-resolved degenerate pump-probe photoluminescence (PL) measurement at room temperature. The suitable excitation range for this time-resolved measurement is in the linear recombination regime as determined from the excitation power dependence of the PL intensity. Carrier lifetimes from this time-resolved measurement are consistent with those obtained from the time correlated single photon counting technique. This study suggests a potential application of this technique to measure the carrier lifetime of QDs in the infrared region with wavelength longer than 1.1 mu m where no high-speed and high sensitivity photon counting devices are available.