Source Themes

[91] Higgs mechanism within a Lawrence-Doniach-type model for layered cuprate superconductors

A relativistic version of the Lawrence-Doniach model is formulated to break the local U(1) gauge symmetry in analogy to the Higgs mechanism. Thereby the global U(1) invariance is spontaneously broken via the superconducting condensate. The resulting …

[89] Ruderman-Kittel-Kasuya-Yosida interaction versus superexchange in a plane in the limit

The indirect exchange interaction between localized Cu spins via mobile O holes is derived from the three-band Anderson lattice model for copper oxides for infinite Hubbard repulsion at Cu sites. By means of two nested canonical transformations, …

[83] Effective vertex of the holon-holon interaction in the t-J model

Within the slave-boson approach to the t-J model of high-Tc superconductivity, the vertex of the spinon-mediated holon-holon interaction is exploited in detail to find out the critical temperature of holon pairing.

[77] On a Unified Canonical Treatment of the Large-Negative- (Positive-) U Hubbard Model

The Schrieffer-Wolff transformation of the large-negative-U Hubbard model is performed in detail. Similarities to and differences from the canonical transformation of the large-positive-U Hamiltonian into the t-J model are discussed.

[69] Conductivity in Anderson-type models: a comparative study of critical disorder

The conductivity in disordered systems is calculated in terms of electron localisation, at dimensionality d=3 and temperature T=0, within tight-binding models with rectangular, Gaussian, Lorentzian and semi-elliptic probability distributions for the …

[52] Incipient localization and tight-binding superconductivity: Tc calculation

Localization effects on the superconducting transition temperature T c are examined in strongly disordered three-dimensional systems. A tight-binding formulation of strong-coupling superconductivity is combined, after configuration averaging, with …

[47] Tc Formula for Strong-Coupling Superconductivity in Random Narrow-Band Alloys

The transition temperature Tc of strong-coupling superconducting alloys AcB1-c is determined with emphasis to tight-binding. Local random Eliashberg-type equations are configuration averaged by means of an effective mass operator on the basis of the …

[32] Superconductivity in a Random Lattice

[24] Ferromagnetic Spin Waves and Their Stability in Disordered Metallic Alloys

[22] On the Spin Wave Theory of Disordered Itinerant-Electron Ferromagnets