The spin-Seebeck effect in a GaMnAs/MnAs bilayer

ORAL

Abstract

The spin-Seebeck effect, recently discovered in ferromagnetic metals such as permalloy, semiconductors such as GaMnAs and insulators such as YIG, consists of a thermally generated spin redistribution. This effect is measured by detecting an inverse spin Hall voltage that varies spatially across a sample due to the thermally generated local spin currents. Here, we describe measurements of the spin-Seebeck effect in metallic ferromagnetic MnAs thin films grown on GaMnAs. The difference in H$_{c}$ and T$_{c}$ of each layer allows independent measurement of spin-Seebeck signals arising from MnAs from that of GaMnAs. We discuss the effect of the exchange bias between these layers on the spin-Seebeck effect above and below the magnetic phase transition. Work support in parts by NSF, NSF-CBET-0754023, ONR, and DMR-0820414.

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Authors

  • Christopher Jaworski

    • Department of Mechanical Engineering, OSU
    • Department of Mechanical Engineering, The Ohio State University

  • Jing Yang

    • Department of Materials Science and Engineering, The Ohio State University

  • Shawn Mack

    • Center for Spintronics and Quantum Computation, University of California, Santa Barbara, CA 93106
    • Center for Spintronics and Quantum Computation, University of California, Santa Barbara

  • D.D. Awschalom

    • Center for Spintronics and Quantum Computation, University of California, Santa Barbara, CA 93106
    • University of California, Santa Barbara
    • University of California Santa Barbara
    • Center for Spintronics and Quantum Computation, University of California, Santa Barbara, CA
    • Center for Spintronics and Quantum Computation, University of California, Santa Barbara
    • Physics Dept., University of California, Santa Barbara CA 93106

  • Joseph Heremans

    • the Ohio State University
    • Department of Mechanical Engineering and Department of Physics, The Ohio State University
    • Ohio State University, Dept of Mechanical Engineering, and Dept. of Physics
    • The Ohio State University
    • Ohio State University
    • Department of Mechanical Engineering and Department of Physics, OSU

  • Roberto Myers

    • Department of Materials Science and Engineering and Department of Physics, The Ohio State University