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Spin accumulation in forward-biased MnAs/GaAs Schottky diodes

J. Stephens·J. Berezovsky·J. P. McGuire·L. J. Sham·A. C. Gossard·D. D. Awschalom
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Abstract

We describe a new means for electrically creating spin polarization in semiconductors. In contrast to spin injection of electrons by tunneling through a reverse-biased Schottky barrier, we observe spin accumulation at the metal/semiconductor interface of forward-biased ferromagnetic Schottky diodes, which is consistent with a theory of spin-dependent reflection off the interface. Spatiotemporal Kerr microscopy is used to image the electron spin and the resulting dynamic nuclear polarization that arises from the non equilibrium carrier polarization.

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J. Stephens, J. Berezovsky, J. P. McGuire, L. J. Sham, A. C. Gossard, D. D. Awschalom. 2004-01-12. Spin accumulation in forward-biased MnAs/GaAs Schottky diodes. https://doi.org/10.1103/physrevlett.93.097602

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