Intrinsic Magnetism in Infinite-Layer Nickelate Superconductors

Nickel and copper are nominally similar so the search for superconductivity in nickelates is a story as old as the quest to understand the high temperature superconductivity of the cuprates.<br/>In this talk, I will introduce the recent discovery of superconductivity in infinite-layer nickelates [1] and the ever-growing family of nickelate superconductors. I will touch on some of the materials challenges involved before summarizing the key physics we have learned so far. In particular I will focus on results from low-energy muon spin rotation [2] that reveals local magnetism in these materials that 1) onsets at rather high temperature, 2) is independent of the rare earth 4f electrons, 3) appears to be robust to doping 4) is antiferromagnetic and possibly short-range-ordered in nature and 5) coexists with superconductivity at low temperatures.<br/>Finally, I will come back to the comparison between nickelates and cuprates and discuss how the disparities in the magnetic properties may be understood.<br/>[1] D. Li et al, Nature 572 (2019) 624<br/>[2] J. Fowlie et al, Nature Physics 18 (2022) 1043