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Electronic Properties of the Effective Singlet-Triplet Model

Maxim M. Korshunov·Sergei G. Ovchinnikov
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Abstract

In present work the effective singlet-triplet model for CuO2-layer on the grounds of multiband p-d model of strongly correlated electrons is obtained. The resulting Hamiltonian has a form of generalized singlet-triplet t-t'-J model for p-type superconductors and form of usual t-t'-J model for n-type superconductors. In the mean field approximation in X-operator representation we derived equations for Gorkov type Green functions. The symmetry classification of the superconducting order parameter in case of tetragonal lattice resulted in d_{x^2-y^2}- and d_{xy}-types of singlet pairing for both p- and n-type superconductors while s-type singlet pairing don't take place. Also normal paramagnetic phase of effective singlet-triplet model was investigated and dispersion over Brillouin zone, density of states and evolution of Fermi level with doping were obtained.

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Maxim M. Korshunov, Sergei G. Ovchinnikov. 2002-08-12. Electronic Properties of the Effective Singlet-Triplet Model. https://arxiv.org/abs/cond-mat/0112447

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