Substrate and cation engineering for optimizing superconductivity in infinite-layer nickelates

Viktor Christiansson; Karsten Held

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arXiv · 2512.20529

Substrate and cation engineering for optimizing superconductivity in infinite-layer nickelates

Viktor Christiansson·Karsten Held

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Abstract

In a recent experiment [Nature 642, 58 (2025)], a new record for the superconducting critical temperature $T_c$ among infinite-layer nickelates has been reported in doped SmNiO$_2$. Here, we use the cutting-edge dynamical vertex approximation (D$\Gamma$A), and qualitatively as well as quantitatively reproduce the $T_c$ vs. doping dome for this compound. Encouraged by this, we go further and identify a path towards realizing even higher $T_c$'s by changing the cation along the line Nd$\rightarrow$Sm$\rightarrow$Y$\rightarrow$Lu with matching substrates. The successively smaller cation radius allows for smaller lattice constants of the substrate. This in turn increases the in-plane hopping and thus eventually $T_c$.

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Viktor Christiansson, Karsten Held. 2025-12-23. Substrate and cation engineering for optimizing superconductivity in infinite-layer nickelates. https://arxiv.org/abs/2512.20529

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