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arXiv · 1211.1682

Solution of the Anderson impurity model via the functional renormalization group

Simon Streib·Aldo Isidori·Peter Kopietz
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Abstract

We show that the functional renormalization group is a numerically cheap method to obtain the low-energy behavior of the Anderson impurity model describing a localized interacting electron coupled to a bath of conduction electrons. Our approach uses an external magnetic field as flow parameter, partial bosonization of the transverse spin fluctuations, and frequency-independent interaction vertices which are fixed by Ward identities. We calculate the quasi-particle residue and the spin susceptibility in the particle-hole symmetric case and obtain excellent agreement with the Bethe ansatz results for arbitrary strengths of the interaction.

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Simon Streib, Aldo Isidori, Peter Kopietz. 2012-11-07. Solution of the Anderson impurity model via the functional renormalization group. https://doi.org/10.1103/physrevb.87.201107

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