Extremely Long Spin-relaxation Of Excitons Localized In Gaas/algaas Coupled Quantum Well Structures

Strong spin polarization has been observed for localized excitons in GaAs/AlGaAs symmetrical double quantum-wells as a function of excitation energy and temperature. The spin relaxation time has been obtained from time-resolved luminescence spectroscopy and turns out to be surprisingly long at low temperatures. A localized nature of the exciton undergoing recombination is invoked in order to explain the observed polarization effects.261222224Uenoyama, T., Sham, L.J., (1990) Phys. Rev. Lett., 64, p. 3070Ferreira, R., Bastard, G., (1991) Phys. Rev., B43, p. 9687Maialle, M.Z., Andrada E Silva, E.A., Sham, L.J., (1993) Phys. Rev., B47, p. 15776Vinattieri, A., Shah, J., Damen, T.C., Kim, D.S., Pfeiffer, L.N., Maialle, M.Z., Sham, L.J., (1994) Phys. Rev., B51, p. 10868Frommer, A., Cohen, E., Ron, A., Pfeiffer, L.N., (1993) Phys. Rev., B48, p. 2803Muñoz, L., Pérez, E., Viña, L., Ploog, K., (1995) Phys. Rev., B51, p. 4247Feldmann, J., Peter, G., Göbel, E.O., Dawson, P., Moore, K., Foxon, G., Elliot, R.J., (1987) Phys. Rev. Lett., 50, p. 2337Roussignol, Ph., Rolland, P., Ferreira, R., Delalande, C., Bastard, G., Vinattieri, A., Carraresi, L., Colocci, M., (1992) Sur. Sci., 276, p. 36