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U-J Synergy Effect for the High Tc Superconductors

Liliana Arrachea·Drazen Zanchi
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Abstract

Using renormalization group and exact diagonalization of small clusters we investigate the ground state phase diagram of a two-dimensional extended Hubbard model with nearest-neighbor exchange interaction J, in addition to the local Coulomb repulsion U. The main instabilities are antiferromagnetism close to half-filling and d-wave superconductivity in the doped system. Our results suggest that the combined action of J and U interactions provide a remarkably efficient mechanism to enhance both d-wave superconducting and antiferromagnetic correlations.

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Liliana Arrachea, Drazen Zanchi. 2004-12-22. U-J Synergy Effect for the High Tc Superconductors. https://doi.org/10.1103/physrevb.71.064519

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