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arXiv · 1012.1732

Optically erasing disorder in semiconductor microcavities with dynamic nuclear polarization

T. C. H. Liew·V. Savona
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Abstract

The mean squared value of the photonic disorder is found to be reduced by a factor of 100 in a typical GaAs based microcavity, when exposed to a circularly polarized continuous wave optical pump without any special spatial patterning. Resonant excitation of the cavity mode excites a spatially non-uniform distribution of spin-polarized electrons, which depends on the photonic disorder profile. Electrons transfer spin to nuclei via the hyperfine contact interaction, inducing a long-living Overhauser magnetic field able to modify the potential of exciton-polaritons.

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T. C. H. Liew, V. Savona. 2011-04-11. Optically erasing disorder in semiconductor microcavities with dynamic nuclear polarization. https://doi.org/10.1103/physrevlett.106.146404

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