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Fermi Liquid without Quasiparticles and Electron Spectral Functions of Two-Dimensional High-$T_c$ Superconductors

V. A. Khodel·M. V. Zverev
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Abstract

Properties of strongly correlated two-dimensional (2D) electron systems in solids are studied on the assumption that these systems undergo a phase transition, called fermion condensation, whose characteristic feature is flattening of the electron spectrum $ε({\pf p})$. Unlike the previous models in the present study, the decay of single-particle states is properly taken into account. Remarkably, the value of the topological charge ($N=1/2$) remains unchanged, supporting the view that systems with a fermion condensate form a separate class of Fermi liquids. Results of calculations are found to be in qualitative agreement with ARPES data.

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V. A. Khodel, M. V. Zverev. 2001-10-22. Fermi Liquid without Quasiparticles and Electron Spectral Functions of Two-Dimensional High-$T_c$ Superconductors. https://doi.org/10.1016/s0921-4526(01)01542-3

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