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Spin-fluctuation mechanism of superconductivity in cuprates

P. Prelovsek·A. Ramsak
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Abstract

The theory of superconductivity within the t-J model, as relevant for cuprates, is developed. It is based on the equations of motion for projected fermionic operators and the mode-coupling approximation for the self-energy matrix. The dynamical spin susceptibility at various doping is considered as an input, extracted from experiments. The analysis shows that the superconductivity onset is dominated by the spin-fluctuation contribution. We show that T_c is limited by the spin-fluctuation scale $Γ$ and shows a pronounced dependence on the next-nearest-neighbor hopping t'. The latter can offer an explanation for the variation of T_c among different families of cuprates.

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P. Prelovsek, A. Ramsak. 2005-02-02. Spin-fluctuation mechanism of superconductivity in cuprates. https://doi.org/10.1103/physrevb.72.012510

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