A strong correlation between zero-temperature superfluid density (ρs0) and transition temperature (Tc) is considered as a hallmark of unconventional superconductivity. However, their relationship has yet to be unveiled in nickelates due to sample inhomogeneity. Here we perform local susceptometry on an infinite-layer nickelate superconductor Nd0.8Sr0.2NiO2. The sample shows inhomogeneous superfluid density and Tc on micron-scale. The spatial statistics for different scan areas reveal a linear dependence of local Tc on ρs0 for Tc>8 K and a sub-linear one for Tc<8 K. Remarkably, the overall relationship is reminiscent of that reported in overdoped cuprate superconductors, hinting at a close connection between them.
@article{arxiv.2601.12676,
title = {Correlation between superfluid density and transition temperature in infinite-layer nickelate superconductor $Nd_{1-x}Sr_xNiO_2$},
author = {Z. J. Li and R . Z. Zhang and M. H. Xu and K. Y. Liang and Y. Zhao and Q. S. He and Q. Z. Zhou and B. R. Chen and P. H. Zhang and K. Z. Yao and H. X. Yao and L. Qiao and Y. H. Wang},
journal= {arXiv preprint arXiv:2601.12676},
year = {2026}
}