A dynamic Jahn-Teller theory for high-Tc superconductivity

M. Weger and R. Englman

Physica A: Statistical Mechanics and its Applications, 1990, vol. 168, issue 1, 324-337

Abstract: The Jahn-Teller effect gives rise to a negative McMillan coupling constant λ. This negative λ gives rise to oscillatory solutions of the BCS gap function Δ(E). The period of oscillations is given (approximately) by 43ω, where ω is the phonon or exciton frequency. These oscillations require an Einstein spectrum, or at least small dispersion. The oscillatory solutions are insensitive to the (non-resonant) Coulomb repulsion μ. They are obtained from the Dyson equation, which serves as a starting point of the Eliashberg theory, but not from the Eliashberg equation per se. We suggest that the singular nature of these solutions requires a minor modification of Eliashberg's derivation. These solutions are particularly favorable for excitonic superconductivity, for which the range of interaction η=32πvF/ω is one, or a few, lattice constants, and the Cooper pairs have some “boson” character. We suggest that these solutions arise because the conditions required for the validity of Migdal's theorem do not hold.

Date: 1990
References: View references in EconPapers View complete reference list from CitEc
Citations:

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/0378437190903845
Full text for ScienceDirect subscribers only. Journal offers the option of making the article available online on Science direct for a fee of $3,000

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:phsmap:v:168:y:1990:i:1:p:324-337

DOI: 10.1016/0378-4371(90)90384-5

Access Statistics for this article

Physica A: Statistical Mechanics and its Applications is currently edited by K. A. Dawson, J. O. Indekeu, H.E. Stanley and C. Tsallis

More articles in Physica A: Statistical Mechanics and its Applications from Elsevier
Bibliographic data for series maintained by Catherine Liu ().