Designing nickelate superconductors with $d^8$ configuration exploiting mixed-anion strategy

Naoya Kitamine; Masayuki Ochi; Kazuhiko Kuroki

doi:10.1103/physrevresearch.2.042032

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arXiv · 2007.01153

Designing nickelate superconductors with $d^8$ configuration exploiting mixed-anion strategy

Naoya Kitamine·Masayuki Ochi·Kazuhiko Kuroki

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Abstract

Inspired by a recently proposed superconducting mechanism for a new cuprate superconductor Ba$_2$CuO$_{3+\delta}$, we theoretically design an unconventional nickelate superconductor with $d^8$ electron configuration. Our strategy is to enlarge the on-site energy difference between $3d_{x^2-y^2}$ and other $3d$ orbitals by adopting halogens or hydrogen as out-of-plane anions, so that the $3d$ bands other than $d_{x^-y^2}$ lie just below the Fermi level for the $d^8$ configuration, acting as incipient bands that enhance superconductivity. We also discuss a possible relevance of the present proposal to the recently discovered superconductor (Nd,Sr)NiO$_2$.

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Naoya Kitamine, Masayuki Ochi, Kazuhiko Kuroki. 2020-07-02. Designing nickelate superconductors with $d^8$ configuration exploiting mixed-anion strategy. https://doi.org/10.1103/physrevresearch.2.042032

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