Time-resolved and time-integrated photoluminescence analysis of state filling and quantum confinement of silicon quantum dots

In this paper we report studies of the optical properties of silicon quantum dot structures. From time-resolved and time-integrated photoluminescence measurements we investigate the state-filling effect and carrier lifetime, and discuss the parabolic confinement of quantum dot structures and the large energy splitting between quantum dot levels. The photoluminescence intensities for different quantum dot levels decay with a stretched exponential function and the decay times are in the range 2–100μs depending on the observation wavelength and the dot size.