SPIN RELAXATION OF EXCITONS IN ZERO-DIMENSIONAL INGAAS QUANTUM DISKS

We report the observation of spin relaxation of excitons in zero-dimen sional semiconductor nanostructures. The spin relaxation is measured i n InGaAs quantum disks by using a polarization dependent time-resolved photoluminescence method. The spin relaxation time in a zero-dimensio nal quantum disk is as long as 0.9 ns at 4 K, which is almost twice as long as the radiative recombination lifetime and is considerably long er than that in quantum wells. The temperature dependence of the spin relaxation time suggests the importance of exciton-acoustic phonon int eraction. (C) 1998 American Institute of Physics.