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Optically-patterned nuclear doughnuts in GaAs/MnAs heterostructures

J. Stephens·J. Berezovsky·R. K. Kawakami·A. C. Gossard·D. D. Awschalom
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Abstract

We demonstrate a scheme for optically patterning nuclear spin polarization in semiconductor/ferromagnet heterostructures. A scanning time-resolved Kerr rotation microscope is used to image the nuclear spin polarization that results when GaAs/MnAs epilayers are illuminated with a focused laser having a Gaussian profile. Rather than tracking the intensity profile of the laser spot, these images reveal that the nuclear polarization forms an annular lateral structure having circular symmetry with a dip rather than a peak at its center.

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J. Stephens, J. Berezovsky, R. K. Kawakami, A. C. Gossard, D. D. Awschalom. 2004-04-10. Optically-patterned nuclear doughnuts in GaAs/MnAs heterostructures. https://doi.org/10.1063/1.1781743

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