Anomalous Behavior of Thermodynamic Properties of Strongly Correlated Fermi Systems

Abstract

Thermodynamic characteristics of Fermi systems are investigated in the vicinity of a phase transition where the effective mass diverges and the single-particle spectrum becomes flat. It is demonstrated that at extremely low temperatures $T$, the flattening of the spectrum is reflected in non-Fermi-liquid behavior of the inverse susceptibility ${\chi }^{-1}(T)\sim T^{\alpha }$ and the specific heat $C(T)/T\sim T^{-\alpha }$, with the critical index $\alpha =2/3$. In the presence of an external static magnetic field $H$, both these quantities are found to exhibit a scaling behavior, e.g. ${\chi }^{-1}(T,H)={\chi }^{-1}(T,0)+T^{2/3}F(H/T)$, in agreement with available experimental data.

4 pages, 2 figures