Measurement of relaxation between polarization eigenstates in single quantum dots

Low temperature relaxation of excitons between polarization eigenstates in single interface fluctuation quantum dots is studied using copolarized and cross-polarized transient differential transmission spectroscopy. The measured spin relaxation times are on the order of similar to100 ps. Such a spin relaxation time is longer than the reported times for thin quantum wells, but considerably shorter than the predicted times for interface fluctuation quantum dots. (C) 2002 American Institute of Physics.