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Anomalous Behavior of Thermodynamic Properties of Strongly Correlated Fermi Systems

J. W. Clark·V. A. Khodel·M. V. Zverev
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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 $χ^{-1}(T) \sim T^α$ and the specific heat $C(T)/T\sim T^{-α}$, with the critical index $α=2/3$. In the presence of an external static magnetic field $H$, both these quantities are found to exhibit a scaling behavior, e.g. $χ^{-1}(T,H)=χ^{-1}(T,0)+ T^{2/3}F(H/T)$, in agreement with available experimental data.

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J. W. Clark, V. A. Khodel, M. V. Zverev. 2004-09-27. Anomalous Behavior of Thermodynamic Properties of Strongly Correlated Fermi Systems. https://doi.org/10.1103/physrevb.71.012401

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