Spin-orbit current-induced torques in (Ga,Mn)As

ORAL

Abstract

Electrical control of magnetic domains has the potential to overcome key challenges to the development of new non-volatile and down-scalable logic and memory devices. We study the spin-orbit torque induced by an unpolarized electric current in the dilute ferromagnetic semiconductor, (Ga,Mn)As. The current-induced torque (CIT) is modeled as the interaction between the uniform magnetization and an effective magnetic field representing the non-equilibrium carrier spin-polarization. We calculate the current-induced field (CIF) using the Kubo linear-response formalism for a broad range of material parameters. We find that the CIF is composed of a dominant term due to the inverse spin galvanic effect and a small component which is dependent on the relative orientation of the current, magnetization, and crystal axes. In conjunction with experimental studies, we investigate the magnetization dynamics using the phenomenological Landau-Lifschitz-Gilbert equation. The study of (Ga,Mn)As opens the door to a comprehensive theory of CITs in uniform magnetic semiconductors.

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Authors

  • Erin K. Vehstedt

    • Texas A\&M University, USA; Institute of Physics, ASCR, CZ

  • Liviu P. Zarbo

    • Institute of Physics, ASCR, CZ

  • Karel Vyborny

    • University at Buffalo-SUNY; Institute of Physics ASCR
    • SUNY Buffalo, USA; Institute of Physics, ASCR, CZ

  • Hidekazu Kurebayashi

    • University of Cambridge, UK

  • Pierre Roy

    • Hitachi Cambridge Laboratory, UK

  • Joerg Wunderlich

    • Hitachi Cambridge Laboratory, UK; Institute of Physics, ASCR, CZ

  • Andrew J. Ferguson

    • University of Cambridge
    • University of Cambridge, UK

  • Tomas Jungwirth

    • Institute of Physics, Academy of Sciences Czech Republic
    • Institue of Physics, ASCR, CZ; University of Nottingham, UK

  • Jairo Sinova

    • Texas A\&M University, USA; Institute of Physics, ASCR, CZ
    • Department of Physics, Texas A\&M University, College Station, Texas 77843-4242, USA