Annalen der Physik

Derivation of Attractive Electron‐Electron Interactions for Superconductivity via Canonical Transformations

E. Kolley, Winfried Kolley

Published Jan 1, 1990• 2 citations

Abstract

Abstract Two canonical transformations, related to the theory of conventional and hightemperature superconductivity are performed in detail. The BCS Hamiltonian is deduced from the Fröhlich Hamiltonian, and the t ‐ J model with attraction from the Hubbard model in the limit of large on‐site Coulomb repulsion. The underlying approximations are pointed out.

DOI: 10.1002/andp.19905020209

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