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Thermodynamic properties of Fermi systems with flat single-particle spectra

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

The behavior of strongly correlated Fermi systems is investigated beyond the onset of a phase transition where the single-particle spectrum $ξ({\bf p})$ becomes flat. The Landau-Migdal quasiparticle picture is shown to remain applicable on the ordered side of this transition. Nevertheless, low-temperature properties evaluated within this picture show profound changes relative to results of Landau theory, as a direct consequence of the flattening of $ξ({\bf p})$. Stability conditions for this class of systems are examined, and the nature of antiferromagnetic quantum phase transitions is elucidated.

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V. A. Khodel, J. W. Clark, M. V. Zverev. 2005-02-11. Thermodynamic properties of Fermi systems with flat single-particle spectra. https://doi.org/10.1209/epl%2Fi2005-10233-9

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