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Exchange Biasing of the Ferromagnetic Semiconductor Ga1-xMnxAs

K. F. Eid·M. B. Stone·K. C. Ku·P. Schiffer·N. Samarth·T. C. Shih·C. J. Palmstrom
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Abstract

We demonstrate the exchange coupling of a ferromagnetic semiconductor (Ga1-xMnxAs) with an overgrown antiferromagnet (MnO). Unlike most conventional exchange biased systems, the blocking temperature of the antiferromagnet (T_B = 48 +- 2 K) and the Curie temperature of the ferromagnet (T_C = 55.1 +- 0.2 K) are comparable. The resulting exchange bias manifests itself as a clear shift in the magnetization hysteresis loop when the bilayer is cooled in the presence of an applied magnetic field and an enhancement of the coercive field.

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K. F. Eid, M. B. Stone, K. C. Ku, P. Schiffer, N. Samarth, T. C. Shih, C. J. Palmstrom. 2004-05-07. Exchange Biasing of the Ferromagnetic Semiconductor Ga1-xMnxAs. https://doi.org/10.1063/1.1787945

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