Consequences of Fermi surface geometry

✍ Scribed by Walter A. Harrison

• Publisher: Elsevier Science
• Year: 1989
• Tongue: English
• Weight: 136 KB
• Volume: 162-164
• Category: Article
• ISSN: 0921-4534
• DOI: 10.1016/0921-4534(89)91251-3

✦ Synopsis

It is assumed that a Fermi surface exists in the high-Tc superconductors and that the interaction V(r) between electrons may be regarded as static. In the tight-binding context, the matrix element of V(r) between band states contains a term equal to the onsite repulsion U , which seriously suppresses superconductivity, especially for low dimensions and short-range interaction. It is seen how this difficulty can be removed in the context of a BCS-like superconducting state, iTk(Uk+vkbk+)/O>, for various Fermi-surface geometries: that for sheets of chains, that for the square geometry appropriate to CuO2 planes, for Fermi surface pockets at the corners of a square antiferromagnetic Brillouin Zone, and for the planar surfaces appropriate to the cubic bismuth-oxide superconductors.