A Superconducting Praseodymium Nickelate with Infinite Layer Structure

A variety of nickel oxide compounds have long been studied for their manifestation of various correlated electron phenomena. Recently, superconductivity was observed in nanoscale infinite layer nickelate thin films of Nd_0.8Sr_0.2NiO₂, epitaxially stabilized on SrTiO₃ substrates via topotactic reduction from the perovskite precursor phase. Here, we present the synthesis and properties of PrNiO₂ thin films on SrTiO3. Upon doping in Pr_0.8Sr_0.2NiO₂, we observe superconductivity with a transition temperature of 7-12 K and robust critical current density at 2 K of 334 kA/cm². These findings indicate that superconductivity in the infinite layer nickelates is relatively insensitive to the details of the rare earth 4f configuration. Furthermore, they motivate the exploration of a broader family of compounds based on two-dimensional NiO₂ planes, which will enable systematic investigation of the superconducting and normal state properties and their underlying mechanisms.