ISSN:
1090-6509
Source:
Springer Online Journal Archives 1860-2000
Topics:
Physics
Notes:
Abstract We show that the anisotropic structure, observed in angle-resolved photoemission spectroscopy experiments, of the gap in high-T c superconductors based on layered cuprate metal-oxide compounds is the result of the strong anisotropy of the electronic spectrum in the plane of the layers, an anisotropy caused by the hybridization between the overlapping broad and anomalously narrow bands. Depending on the values of the electron-phonon coupling constants and the Coulomb repulsion, which in certain conditions is balanced almost perfectly by the attraction caused by the electron-plasmon interaction, either the $$d_{x^2 - y^2 } $$ or the s xy symmetry is realized in the superconducting order parameter. When the initial C v4 symmetry of the band spectrum of the Bi(2212) single crystal with a superlattice or the Y(123) single crystal with one-dimensional chains is broken, an anomalous temperature dependence of the anisotropic-gap width Δ is observed, and this dependence differs dramatically from the standard Δ (T) dependence of the BCS theory.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1134/1.558136
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