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Exciton spin relaxation in InAs/InGaAlAs/InP(001) quantum dashes emitting near 1.55 {mu}m

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 نشر من قبل Micha{\\l} Gawe{\\l}czyk M.Sc.
 تاريخ النشر 2018
  مجال البحث فيزياء
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Exciton spin and related optical polarization in self-assembled InAs/In$_{0.53}$Ga$_{0.23}$Al$_{0.24}$As/InP(001) quantum dashes emitting at 1.55 {mu}m are investigated by means of polarization- and time-resolved photoluminescence, as well as photoluminescence excitation spectroscopy, at cryogenic temperature. We investigate the influence of highly non-resonant and quasi-resonant optical spin pumping conditions on spin polarization and spin memory of the quantum dash ground state. We show that a spin pumping scheme, utilizing the longitudinal-optical-phonon-mediated coherent scattering process, can lead to the polarization degree above 50%. We discuss the role of intrinsic asymmetries in the quantum dash that influence values of the degree of polarization and its time evolution.



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