Harmonic expansion of the effective potential in Functional   Renormalization Group at finite chemical potential
  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. 
G.G. Barnafoldi, A. Jakovac, P. Posfay
hep-th hep-ph