Loughborough University
Browse
0301541.pdf (1.07 MB)

Superlight bipolarons and criterion of BCS-BEC crossover in cuprates

Download (1.07 MB)
preprint
posted on 2006-04-03, 15:51 authored by A.S. Alexandrov
Most of the proposed models of high-temperature superconductivity (HTSC) are based on the short-range electron-electron correlations or/and on a short-range electron-phonon interaction. However, in the cuprates the screening is poor due to a low carrier density, layered crystal structure, and high ionicity of the lattice. We develop further the bipolaron model of HTSC, which explicitly takes into account the long-range origin of all interactions. The long-range electron-phonon (Froehlich) interaction binds carriers into real space pairs (small bipolarons) with surprisingly low mass but sufficient binding energy, while the long-range Coulomb repulsion keeps them from forming larger clusters. The model has explained many key features of cuprates. Here it is shown that real-space pairing takes place in many cuprates at variance with some (incorrect) criteria of the BCS-BEC crossover.

History

School

  • Science

Department

  • Physics

Pages

1124074 bytes

Publication date

2003

Notes

This is a pre-print. The definitive version: ALEXANDROV, A.S., 2003. Superlight bipolarons and criterion of BCS-BEC crossover in cuprates. International Journal of Modern Physics, B17(18-20), pp. 3315-3318.

Language

  • en

Usage metrics

    Loughborough Publications

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC