Dynamics of bright and dark excitons in a self-assembled quantum dot
We report on a spin-flip process in a charge tunable quantum dot in which a non-radiative dark exciton, with angular momentum L = 2, becomes a radiative bright exciton, L = 1, through interactions with a Fermi sea in an n-doped back contact. This process presents itself by a strongly bias dependent...
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| Materiálatiipa: | Conference item |
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2005
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| Čoahkkáigeassu: | We report on a spin-flip process in a charge tunable quantum dot in which a non-radiative dark exciton, with angular momentum L = 2, becomes a radiative bright exciton, L = 1, through interactions with a Fermi sea in an n-doped back contact. This process presents itself by a strongly bias dependent secondary lifetime in radiative lifetime measurements of the neutral exciton. By studying dots with different emission energies the spin-flip process is shown to have a strong dependence on the tunneling rate between the dot and the back contact. An Anderson-like Hamiltonian is used to model a coherent spin swap process between an electron in the dot and electrons in the back contact and gives very good agreement with the experiment. © 2005 American Institute of Physics. |
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