Spin-transfer torque magnetization reversal in uniaxial nanomagnets with thermal noise

D. Pinna, A. D. Kent, D. L. Stein

    Research output: Contribution to journalArticle

    Abstract

    We consider the general Landau-Lifshitz-Gilbert (LLG) dynamical theory underlying the magnetization switching rates of a thin film uniaxial magnet subject to spin-torque effects and thermal fluctuations. After discussing the various dynamical regimes governing the switching phenomena, we present analytical results for the mean switching time behavior. Our approach, based on explicitly solving the first passage time problem, allows for a straightforward analysis of the thermally assisted, low spin-torque, switching asymptotics of thin film magnets. To verify our theory, we have developed an efficient Graphics Processing Unit (GPU)-based micromagnetic code to simulate the stochastic LLG dynamics out to millisecond timescales. We explore the effects of geometrical tilts between the spin-current and uniaxial anisotropy axes on the thermally assisted dynamics. We find that even in the absence of axial symmetry, the switching times can be functionally described in a form virtually identical to the collinear case.

    Original languageEnglish (US)
    Article number033901
    JournalJournal of Applied Physics
    Volume114
    Issue number3
    DOIs
    StatePublished - Jul 21 2013

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    thermal noise
    torque
    magnetization
    magnets
    thin films
    anisotropy
    symmetry

    ASJC Scopus subject areas

    • Physics and Astronomy(all)

    Cite this

    Spin-transfer torque magnetization reversal in uniaxial nanomagnets with thermal noise. / Pinna, D.; Kent, A. D.; Stein, D. L.

    In: Journal of Applied Physics, Vol. 114, No. 3, 033901, 21.07.2013.

    Research output: Contribution to journalArticle

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