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arXiv · 1503.08164

Superconductivity from emerging magnetic moments

Shintaro Hoshino·Philipp Werner
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Abstract

Multi-orbital Hubbard models are shown to exhibit a spatially isotropic spin-triplet superconducting phase, where equal-spin electrons in different local orbitals are paired. This superconducting state is stabilized in the spin-freezing crossover regime, where local moments emerge in the metal phase, and the pairing is substantially assisted by spin anisotropy. The phase diagram features a superconducting dome below a non-Fermi liquid metallic region and next to a magnetically ordered phase. We suggest that this type of fluctuating-moment induced superconductivity, which is not originating from fluctuations near a quantum critical point, may be realized in spin-triplet superconductors such as strontium ruthenates and uranium compounds.

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Shintaro Hoshino, Philipp Werner. 2015-12-09. Superconductivity from emerging magnetic moments. https://doi.org/10.1103/physrevlett.115.247001

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