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arXiv · 2205.00919

Review of recent developments of the functional renormalization group for systems out of equilibrium

G. Camacho·C. Klöckner·D. M. Kennes·C. Karrasch
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Abstract

We recapitulate recent developments of the functional renormalization group (FRG) approach to the steady state of systems out of thermal equilibrium. In particular, we discuss second-order truncation schemes which account for the frequency-dependence of the two particle vertex and which incorporate inelastic processes. Our focus is on two different types of one-dimensional fermion chains: i) infinite, open systems which feature a translation symmetry, and ii) finite systems coupled to left and right reservoirs. In addition to giving a detailed and unified review of the technical derivation of the FRG schemes, we briefly summarize some of the key physical results. In particular, we compute the non-equilibrium phase diagram and analyze the fate of the Berezinskii-Kosterlitz-Thouless transition in the infinite, open system.

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G. Camacho, C. Klöckner, D. M. Kennes, C. Karrasch. 2022-12-02. Review of recent developments of the functional renormalization group for systems out of equilibrium. https://doi.org/10.1140/epjb%2Fs10051-022-00445-3

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