Reduced model for precessional switching of thin-film nanomagnets under the influence of spin torque

Ross G. Lund, Gabriel D. Chaves-O'Flynn, Andrew D. Kent, Cyrill B. Muratov

    Research output: Contribution to journalArticle

    Abstract

    We study the magnetization dynamics of thin-film magnetic elements with in-plane magnetization subject to a spin current flowing perpendicular to the film plane. We derive a reduced partial differential equation for the in-plane magnetization angle in a weakly damped regime. We then apply this model to study the experimentally relevant problem of switching of an elliptical element when the spin polarization has a component perpendicular to the film plane, restricting the reduced model to a macrospin approximation. The macrospin ordinary differential equation is treated analytically as a weakly damped Hamiltonian system, and an orbit-averaging method is used to understand transitions in solution behaviors in terms of a discrete dynamical system. The predictions of our reduced model are compared to those of the full Landau-Lifshitz-Gilbert-Slonczewski equation for a macrospin.

    Original languageEnglish (US)
    Article number144425
    JournalPhysical Review B - Condensed Matter and Materials Physics
    Volume94
    Issue number14
    DOIs
    StatePublished - Oct 20 2016

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    torque
    Magnetization
    Torque
    Thin films
    magnetization
    thin films
    Magnetic thin films
    Hamiltonians
    Spin polarization
    Ordinary differential equations
    partial differential equations
    dynamical systems
    Partial differential equations
    Dynamical systems
    Orbits
    differential equations
    orbits
    polarization
    predictions
    approximation

    ASJC Scopus subject areas

    • Electronic, Optical and Magnetic Materials
    • Condensed Matter Physics

    Cite this

    Reduced model for precessional switching of thin-film nanomagnets under the influence of spin torque. / Lund, Ross G.; Chaves-O'Flynn, Gabriel D.; Kent, Andrew D.; Muratov, Cyrill B.

    In: Physical Review B - Condensed Matter and Materials Physics, Vol. 94, No. 14, 144425, 20.10.2016.

    Research output: Contribution to journalArticle

    Lund, Ross G. ; Chaves-O'Flynn, Gabriel D. ; Kent, Andrew D. ; Muratov, Cyrill B. / Reduced model for precessional switching of thin-film nanomagnets under the influence of spin torque. In: Physical Review B - Condensed Matter and Materials Physics. 2016 ; Vol. 94, No. 14.
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