Spin fluctuations sufficient to mediate superconductivity in nickelates

Paul Worm; Qisi Wang; Motoharu Kitatani; Izabela Biało; Qiang Gao; Xiaolin Ren; Jaewon Choi; Diana Csontosová; Ke-Jin Zhou; Xingjiang Zhou; Zhihai Zhu; Liang Si; Johan Chang; Jan M. Tomczak; Karsten Held

arXiv · 2312.08260

Spin fluctuations sufficient to mediate superconductivity in nickelates

Paul Worm·Qisi Wang·Motoharu Kitatani·Izabela Biało·Qiang Gao·Xiaolin Ren·Jaewon Choi·Diana Csontosová·Ke-Jin Zhou·Xingjiang Zhou·Zhihai Zhu·Liang Si·Johan Chang·Jan M. Tomczak·Karsten Held

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Abstract

Infinite-layer nickelates show high-temperature superconductivity, and the experimental phase diagram agrees well with the one simulated within the dynamical vertex approximation (D$\Gamma$A). Here, we compare the spin-fluctuation spectrum behind these calculations to resonant inelastic X-ray scattering experiments. The overall agreement is good. This independent cross-validation of the strength of spin fluctuations strongly supports the scenario, advanced by D$\Gamma$A, that spin-fluctuations are the mediator of the superconductivity observed in nickelates.

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Paul Worm, Qisi Wang, Motoharu Kitatani, Izabela Biało, Qiang Gao, Xiaolin Ren, Jaewon Choi, Diana Csontosová, Ke-Jin Zhou, Xingjiang Zhou, Zhihai Zhu, Liang Si, Johan Chang, Jan M. Tomczak, Karsten Held. 2023-12-13. Spin fluctuations sufficient to mediate superconductivity in nickelates. https://arxiv.org/abs/2312.08260

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