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arXiv · 0804.4458

Magnetic field induced rotation of the d-vector in the spin triplet superconductor Sr$_2$RuO$_4$

Abstract

In zero magnetic field the superconductor Sr$_2$RuO$_4$ is believed to have a chiral spin triplet pairing state in which the gap function d-vector is aligned along the crystal c-axis. Using a phenomenological but orbital specific description of the spin dependent electron-electron attraction and a realistic quantitative account of the electronic structure in the normal state we analyze the orientation of the spin triplet Cooper pair d-vector in response to an external c-axis magnetic field. We show that for suitable values of the model parameters a c-axis field of only 20 mT is able to cause a reorientation phase transition of the d-vector from along $c$ to the $a-b$ plane, in agreement with recent experiments.

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James F. Annett, B. L. Györffy, G. Litak, K. I. Wysokiński. 2008-04-28. Magnetic field induced rotation of the d-vector in the spin triplet superconductor Sr$_2$RuO$_4$. https://doi.org/10.1103/physrevb.78.054511

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