Superconductivity in a Toy Model of the Pseudogap State

E. Z. Kuchinskii; M. V. Sadovskii

doi:10.1134/1.559136

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Superconductivity in a Toy Model of the Pseudogap State

E. Z. Kuchinskii·M. V. Sadovskii

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Abstract

We analyze superconducting state (both s and d - wave) in a simple exactly solvable model of pseudogap state, induced by short - range order fluctuations (e.g. antiferromagnetic), which is based upon model Fermi - surface with "hot patches". It is shown that superconducting energy gap averaged over these fluctuations is non zero even for the temperatures larger than mean - field T_c of superconducting transition in a sample as a whole. For temperatures T>T_c superconductivity apparently exists within separate regions ("drops"). We study the spectral density and the density of states and demonstrate that superconductivity signals itself in these already for T>T_c, while at T_c itself nothing special happens from this point of view. These anomalies are in qualitative agreement with a number experiments on underdoped cuprates.

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E. Z. Kuchinskii, M. V. Sadovskii. 1999-10-18. Superconductivity in a Toy Model of the Pseudogap State. https://doi.org/10.1134/1.559136

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