ORIGIN OF CURIE–WEISS LAW IN GINZBURG–LANDAU FUNCTIONAL

Abstract

We investigate the Ginzburg–Landau (GL) functional to infinite orders. The GL functional can be substituted for a renormalized infinite series method (RISM). The Curie–Weiss law happens only if the GL functioal has a divergence using an adjustable infinite series. It is shown that the superconducting gap is not contributed by phase fluctuations in cuprate superconductors using the RISM. The results by the RISM applied to ferroelectric materials are similar to those by the GL theory. For ferromagnetic materials, the RISM is equivalent to the GL theory, and is applied to functionals to show a Curie–Weiss type susceptibility, χ.