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Anomalous Behavior of the Spin Susceptibility of Strongly Correlated Fermi Systems

J. W. Clark·V. A. Khodel·M. V. Zverev
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Abstract

The spin susceptibility $χ(T)$ of strongly correlated Fermi systems is investigated in the density region where Fermi-liquid theory fails. We attribute this failure to a specific quantum phase transition associated with a rearrangement of the Landau state at low temperatures $T$, retaining the assumption that the Landau quasiparticle picture survives in a generic sense. Taking into account the resulting modification of the quasiparticle istribution function, the spin susceptibility $χ(T)$ is shown to contain a Curie-Weiss component $χ_{\rm CW}(T)\sim (T-Θ_{\rm W})^{-1}$, with the Weiss temperature $Θ_{\rm W}$ vanishing at the critical density for the transition.

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J. W. Clark, V. A. Khodel, M. V. Zverev. 2004-03-19. Anomalous Behavior of the Spin Susceptibility of Strongly Correlated Fermi Systems. https://arxiv.org/abs/cond-mat/0403522

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