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arXiv · 2210.09098

Dominant superconducting correlations in a Luttinger liquid induced by spin fluctuations

Niels Henrik Aase·Asle Sudbø
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Abstract

We study spin-fluctuation mediated divergent superconducting fluctuations in a Luttinger liquid proximity-coupled to a spin chain. Our study provides insight into how spin fluctuations can induce superconductivity in a strongly correlated non-Fermi liquid with repulsive electronic interactions only. The electrons in the system are governed by the Extended Hubbard Hamiltonian and are coupled to a chain of localized spins modeled by the spin-$\frac{1}{2}$ $XX$ Hamiltonian. Using a multichannel Luttinger liquid approach, we determine the phase diagram of the metal chain. We find that spin-polarized triplet superconducting correlations persist for repulsive electronic interactions for sufficiently large interchain couplings.

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Niels Henrik Aase, Asle Sudbø. 2022-10-17. Dominant superconducting correlations in a Luttinger liquid induced by spin fluctuations. https://doi.org/10.1103/physrevb.106.l241102

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