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arXiv · 1108.4023

Adaptation of the Landau-Migdal Quasiparticle Pattern to Strongly Correlated Fermi Systems

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

A quasiparticle pattern advanced in Landau's first article on Fermi liquid theory is adapted to elucidate the properties of a class of strongly correlated Fermi systems characterized by a Lifshitz phase diagram featuring a quantum critical point (QCP) where the density of states diverges. The necessary condition for stability of the Landau Fermi Liquid state is shown to break down in such systems, triggering a cascade of topological phase transitions that lead, without symmetry violation, to states with multi-connected Fermi surfaces. The end point of this evolution is found to be an exceptional state whose spectrum of single-particle excitations exhibits a completely flat portion at zero temperature. Analysis of the evolution of the temperature dependence of the single-particle spectrum yields results that provide a natural explanation of classical behavior of this class of Fermi systems in the QCP region.

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V. A. Khodel, J. W. Clark, M. V. Zverev. 2011-08-19. Adaptation of the Landau-Migdal Quasiparticle Pattern to Strongly Correlated Fermi Systems. https://doi.org/10.1134/s1063778811090079

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