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arXiv · 1610.06824

The renormalized superperturbation theory (SPT) approach to the Anderson model in and out of equilibrium

Enrique Muñoz·Farzaneh Zamani·Lukas Merker·Theo Costi·Stefan Kirchner
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Abstract

The properties of current-carrying steady states of strongly correlated systems away from the linear-response regime are of topical interest. In this article, we review the renormalized perturbation theory, or renormalized SPT of reference [1] for the Anderson model. We present an extension to higher orders and compare the higher-order results with NRG calculations. Finally, we elucidate the role of Ward identities in calculating out-of-equilibrium properties and address claims made in the literature.

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Enrique Muñoz, Farzaneh Zamani, Lukas Merker, Theo Costi, Stefan Kirchner. 2016-10-21. The renormalized superperturbation theory (SPT) approach to the Anderson model in and out of equilibrium. https://doi.org/10.1088/1742-6596%2F807%2F9%2F092001

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