A Superconducting Praseodymium Nickelate with Infinite Layer Structure

TLDR

Nickel oxides have long exhibited correlated electron phenomena, and superconductivity was recently discovered in Nd0.8Sr0.2NiO2 infinite‑layer thin films grown on SrTiO3 via topotactic reduction. The study reports the synthesis and characterization of PrNiO2 thin films on SrTiO3 and proposes extending the family of infinite‑layer nickelates to probe superconducting and normal‑state properties. Doped Pr0.8Sr0.2NiO2 thin films become superconducting with Tc = 7–12 K and a 2 K critical current density of 334 kA cm⁻², showing that superconductivity is largely independent of the rare‑earth 4f configuration.

Abstract

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 Nd0.8Sr0.2NiO2, 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 Pr0.8Sr0.2NiO2, 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.