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Comparison of superconductivity in Sr_2RuO_4 and copper oxides

E. V. Kuz'min·S. G. Ovchinnikov
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Abstract

To compare the superconductivity in strongly correlated electron systems with the antiferromagnetic fluctuations in the copper oxides and with the ferromagnetic fluctuations in Sr_2RuO_4 a t-J-I model is proposed. The antiferromagnetic coupling J results in the superconducting state of d_{x^2-y^2} symmetry and the ferromagnetic coupling constant I results in the spin-triplet p-type state. The difference in the gap anisotropies provides the large difference in T_c values, for the typical values of the coupling constants: T_c of order of 1K for the ruthenate and T_c of order of 100K for the cuprates.

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E. V. Kuz'min, S. G. Ovchinnikov. 1999-03-20. Comparison of superconductivity in Sr_2RuO_4 and copper oxides. https://doi.org/10.1103/physrevb.61.15392

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