1 N expansion of the nonequilibrium infinite- U Anderson model

Zurab Ratiani, Aditi Mitra

    Research output: Contribution to journalArticle

    Abstract

    Results are presented for the nonequilibrium infinite- U Anderson model using a large N approach, where N is the degeneracy of the impurity level, and where nonequilibrium is established by coupling the level to two leads at two different chemical potentials so that there is current flow. A slave-boson representation combined with Keldysh functional integral methods is employed. Expressions for the static spin susceptibility χS and the conductance G are presented to O (1 N) and for an applied voltage difference V less than the Kondo temperature. The correlation function for the slave boson is found to be significantly modified from its equilibrium form in that it acquires a rapid decay in time with a rate that equals the current-induced decoherence rate. Physical observables are found to have a rather complex dependence on the coupling strength to the two leads which can lead to asymmetric behavior χS (V) χS (-V), G (V) G (-V) both in the mixed valence and in the Kondo regime.

    Original languageEnglish (US)
    Article number245111
    JournalPhysical Review B - Condensed Matter and Materials Physics
    Volume79
    Issue number24
    DOIs
    StatePublished - Jun 8 2009

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    Bosons
    bosons
    expansion
    Chemical potential
    Induced currents
    Impurities
    valence
    magnetic permeability
    impurities
    Electric potential
    electric potential
    decay
    Temperature
    temperature

    ASJC Scopus subject areas

    • Condensed Matter Physics
    • Electronic, Optical and Magnetic Materials

    Cite this

    1 N expansion of the nonequilibrium infinite- U Anderson model. / Ratiani, Zurab; Mitra, Aditi.

    In: Physical Review B - Condensed Matter and Materials Physics, Vol. 79, No. 24, 245111, 08.06.2009.

    Research output: Contribution to journalArticle

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