SearcharxivSearch

arXiv subjects

N. Plakida

Publications and source records attributed to N. Plakida.

2 recordsLinked to original sources

On the Coulomb interaction in superconducting pairing in cuprates

We discuss a reduction of superconducting transition temperature by the intersite Coulomb repulsion for the d-wave pairing in cuprates. We compare the results found for the spin-fermion model and the extended Hubbard model. We argue that in both the models the d-wave superconducting transition temperature is reduced by the Coulomb repulsion of holes in different unit cells. We also show that in the strong correlation limit the s-wave superconductivity cannot occur due to the kinematic restriction of no double occupancy in the Hubbard subbands.

cond-mat.str-el

Electronic spectrum in cuprates within p-d Hubbard model

A microscopic theory for electronic spectrum of the CuO2 plane within an effective p-d Hubbard model is proposed. Dyson equation for the one-electron Green function in terms of the Hubbard operators is derived which is solved self-consistently for the self-energy evaluated in the noncrossing approximation. Electron scattering on spin fluctuations induced by kinematical interaction is described by a model dynamical spin susceptibility. Doping and temperature dependence of electron dispersions, spectral functions, the Fermi surface and the coupling constant are studied.

cond-mat.str-el