Superconductivity in infinite-layer nickelates*

Finding unconventional superconductors in proximity to various strongly correlated electronic phases has been a recurring theme in materials as diverse as heavy fermion compounds, cuprates, pnictides, and twisted bilayer graphene. The recent discovery of superconductivity in layered nickelates¹ was motivated by looking for an analog of the cuprates. The synthesis of the nickelates is in and of itself interesting – it involves the removal of planes of oxygen from a 3D nickel oxide using soft chemistry techniques. We will introduce this new family of superconductors and our current understanding of their electronic and magnetic structure. Notable aspects are a doping-dependent superconducting dome², strong magnetic fluctuations³, instabilities towards charge stripes⁴, and a landscape of unusual normal state properties from which superconductivity emerges⁵. These features are strongly reminiscent of the cuprates, despite key differences in the electronic structure and the absence of a proximate correlated insulator.

 

¹D. F. Li et al., Nature 572, 624 (2019).

²D. F. Li et al., Phys. Rev. Lett. 125, 027001 (2020).

³H. Lu et al., Science 373, 213 (2021).

⁴M. Rossi et al., Nat. Phys. 18, 869 (2022).

⁵K. Lee et al., arXiv: 2203.02580.