Unified static renormalization-group treatment of finite-temperature crossovers close to a quantum critical point

Abstract

A non conventional Renormalization Group treatment close and below four dimensions is used to explore the low temperature properties of a wide class of systems in the influence domain of their quantum critical point. The approach consists in a preliminary averaging over quantum degrees of freedom and a successive employment of the Wilsonian RG trasformation to treat the resulting effective Ginzburg-Landau free energy functional. Thia allows a detailed study of criticality of the quantum systems.