Ac- and dc-driven noise and I-V characteristics of magnetic nanostructures

O. A. Tretiakov, Aditi Mitra

    Research output: Contribution to journalArticle

    Abstract

    We study a structure consisting of a ferromagnetic (F) layer coupled to two normal metal (N) leads. The system is driven out of equilibrium by the simultaneous application of external dc and ac voltages across the N/F/N structure. Using the Keldysh diagrammatic approach, and modeling the ferromagnet as a classical spin of size S≫1, we derive the Langevin equation for the magnetization dynamics and calculate the noise correlator. We find that the noise has an explicit frequency dependence in addition to depending on the characteristics of the ac and dc drive. Further, we calculate the current-voltage characteristics of the structure to Ω(1/S2) and find that the nonequilibrium dynamics of the ferromagnetic layer gives rise to corrections to the current that are both linear and nonlinear in voltage.

    Original languageEnglish (US)
    Article number024416
    JournalPhysical Review B - Condensed Matter and Materials Physics
    Volume81
    Issue number2
    DOIs
    StatePublished - Jan 22 2010

    Fingerprint

    Nanostructures
    F region
    Correlators
    Electric potential
    electric potential
    Current voltage characteristics
    Magnetization
    Metals
    correlators
    magnetization
    metals

    ASJC Scopus subject areas

    • Condensed Matter Physics
    • Electronic, Optical and Magnetic Materials

    Cite this

    Ac- and dc-driven noise and I-V characteristics of magnetic nanostructures. / Tretiakov, O. A.; Mitra, Aditi.

    In: Physical Review B - Condensed Matter and Materials Physics, Vol. 81, No. 2, 024416, 22.01.2010.

    Research output: Contribution to journalArticle

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