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arXiv · 1604.01717

Harmonic expansion of the effective potential in Functional Renormalization Group at finite chemical potential

G. G. Barnafoldi·A. Jakovac·P. Posfay
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Abstract

In this paper we propose a method to study the Functional Renormalization Group at finite chemical potential. The method consists of mapping the FRG equations within the Fermi surface into a differential equation defined on a rectangle with zero boundary conditions. To solve this equation we use an expansion of the potential in a harmonic basis. With this method we determined the phase diagram of a simple Yukawa-type model; as expected, the bosonic fluctuations decrease the strength of the transition.

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G. G. Barnafoldi, A. Jakovac, P. Posfay. 2016-04-06. Harmonic expansion of the effective potential in Functional Renormalization Group at finite chemical potential. https://doi.org/10.1103/physrevd.95.025004

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