Hybridization-induced wide-band bipolaron model for high-Tcsuperconductors
- 1 June 1987
- journal article
- research article
- Published by Taylor & Francis in Philosophical Magazine Letters
- Vol. 55 (6) , 251-256
- https://doi.org/10.1080/09500838708214693
Abstract
A microscopic theory based on the idea of hybridization-induced wide-band bipolarons is proposed to explain the occurrence of high-temperature superconductors such as La2−x-BaxCuO4, and La2−xSrxCuO4. In our view, these are such that bipolarons are formed whose singlet ground state possesses a large binding energy (Δ) with bandwidth W (>Δ) as a result of two distinct electron-phonon mechanisms and two types of hybridization between Cu2+ d electrons and other electrons. This wide-band bipolaron gas has features similar to Cooper pairs and leads to a superconducting state with high Tc in which all occupied electron states participate. The large electron-phonon coupling and a large W both cause the transition temperature Tc, to rise spectacularly.Keywords
This publication has 6 references indexed in Scilit:
- Superconductivity at high temperatures in doped oxidesNature, 1987
- Evidence for superconductivity above 40 K in the La-Ba-Cu-O compound systemPhysical Review Letters, 1987
- Properties of Bipolaron SystemJournal of the Physics Society Japan, 1983
- Theory of bipolarons and bipolaronic bandsPhysical Review B, 1981
- Structural instability and superconductivity in A-15 compoundsReviews of Modern Physics, 1975
- Electron correlations in narrow energy bandsProceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences, 1963