Luminescence decay dynamics of germanium nanocrystals in silicon

The dynamics of the luminescence decay from germanium nanocrystals embedded in crystalline silicon has been studied for temperatures varied between 16 K and room temperature. At room temperature the characteristic decay time is of the order of 50 nanoseconds while it extends into the microsecond range at low temperatures. The decay is dominated by non-radiative processes, which show a typical thermal activation energy of a few meV.