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Low temperature electronic properties of Sr_2RuO_4 II: Superconductivity

Ralph Werner
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Abstract

The body centered tetragonal structure of Sr_2RuO_4 gives rise to umklapp scattering enhanced inter-plane pair correlations in the d_{yz} and d_{zx} orbitals. Based on symmetry arguments, Hund's rule coupling, and a bosonized description of the in-plane electron correlations the superconducting order parameter is found to be a orbital-singlet spin-triplet with two spatial components. The spatial anisotropy is 7%. The different components of the order parameter give rise to two-dimensional gapless fluctuations. The phase transition is of third order. The temperature dependence of the pair density, specific heat, NQR, Knight shift, and susceptibility are in agreement with experimental results.

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Ralph Werner. 2002-08-15. Low temperature electronic properties of Sr_2RuO_4 II: Superconductivity. https://doi.org/10.1103/physrevb.67.014505

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