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Semiclassical analysis of the Nonequilibrium Local Polaron

A. Mitra·I. Aleiner·A. J. Millis
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Abstract

A resonant level strongly coupled to a local phonon under nonequilibrium conditions is investigated. The nonequilibrium Hartree-Fock approximation is shown to correspond to approximating the steady state density matrix by delta functions at field values to which the local dynamics relaxes in a semiclassical limit. If multiple solutions exist, all are shown to make nonvanishing contributions to physical quantities: multistability does not exist. Nonequilibrium effects are shown to produce decoherence, causing the standard expansions to converge and preventing the formation of a polaron feature in the spectral function. The formalism also applies to the nonequilibrium Kondo problem.

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A. Mitra, I. Aleiner, A. J. Millis. 2004-09-09. Semiclassical analysis of the Nonequilibrium Local Polaron. https://doi.org/10.1103/physrevlett.94.076404

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