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Functional renormalization group for non-equilibrium quantum many-body problems

R. Gezzi·Th. Pruschke·V. Meden
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Abstract

We extend the concept of the functional renormalization for quantum many-body problems to non-equilibrium situations. Using a suitable generating functional based on the Keldysh approach, we derive a system of coupled differential equations for the $m$-particle vertex functions. The approach is completely general and allows calculations for both stationary and time-dependent situations. As a specific example we study the stationary state transport through a quantum dot with local Coulomb correlations at finite bias voltage employing two different truncation schemes for the infinite hierarchy of equations arising in the functional renormalization group scheme.

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R. Gezzi, Th. Pruschke, V. Meden. 2006-11-23. Functional renormalization group for non-equilibrium quantum many-body problems. https://doi.org/10.1103/physrevb.75.045324

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