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arXiv · 2207.04388

Impacts of f-d Kondo cloud on superconductivity of nickelates

Byungkyun Kang·Hyunsoo Kim·Qiang Zhu·Chul Hong Park
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Abstract

The discovery of superconducting nickelates reignited hope for elucidating the high-$T_{\textrm{c}}$ superconductivity mechanism in the isostructural cuprates. While in the cuprates, the superconducting gap opens up on a single-band of the quasi-2D Fermi surface, the nickelates are known to have 3D nature of electronic structure with multi-band. This raises a serious question about the role of 2D nature for the high-$T_{\textrm{c}}$ superconductivity. Here, employing dynamical mean field theory combined with GW method, we found the Kondo effect driven by the strong correlation of Nd-4$f$ and Ni-3$d$ electrons emerging at low temperature. The Kondo effect modifies the topology of the Fermi surface leading to 3D multi-band nature. Remarkably, the Kondo effect is easily destroyed by lattice modulation, leading to the quasi-2D nature. Our findings clearly explain the inconsistent occurrence of superconductivity and distinct electrical resistivity behavior between NdNiO$_{2}$ bulk and films.

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Byungkyun Kang, Hyunsoo Kim, Qiang Zhu, Chul Hong Park. 2022-07-10. Impacts of f-d Kondo cloud on superconductivity of nickelates. https://arxiv.org/abs/2207.04388

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