Curie law, entropy excess, and superconductivity in heavy fermion metals and other strongly interacting Fermi liquids

TL;DR

This paper explores the thermodynamic behavior of strongly interacting Fermi liquids, revealing Curie-Weiss susceptibility and entropy features, and explains how these properties influence superconductivity, with experimental validation on heavy fermion metals and helium films.

Contribution

It introduces a theoretical framework linking entropy excess and Curie law behavior to superconductivity in heavy fermion systems and other Fermi liquids.

Findings

Spin susceptibility follows Curie-Weiss law.

Entropy includes a temperature-independent term.

Superconducting transition releases excess entropy, affecting specific heat.

Abstract

Low-temperature thermodynamic properties of strongly interacting Fermi liquids with fermion condensate are investigated. We demonstrate that the spin susceptibility of these systems exhibits the Curie-Weiss law, and the entropy contains a temperature-independent term. The excessive entropy is released at the superconducting transition, enhancing the specific heat jump Delta C and rendering it proportional to the effective Curie constant. The theoretical results are favorably compared with the experimental data on the heavy fermion metal CeCoIn5, as well as He-3 films.