Journal Article

Electronic structure of the parent compound of superconducting infinite-layer nickelates

Hwang, H. Y., Huang, H. Y., Zhou, K. J., Zaanen, J., Jia, C. J., Lee, W. S., Rossi, M., Been, E., Nag, A., Garcia-Fernandez, M., Osada, M., Shen, Z. X., Huang, D. J., Moritz, B., Tseng, Y., Hussain, Z., Schmitt, T., Devereaux, T. P., Lu, H., Li, D., Hikita, Y., Paris, E., Chuang, Y.-D., Hepting, M., Feng, X.

2020

Overview

The search continues for nickel oxide-based materials with electronic properties similar to cuprate high-temperature superconductors 1 – 10 . The recent discovery of superconductivity in the doped infinite-layer nickelate NdNiO 2 (refs. 11 , 12 ) has strengthened these efforts. Here, we use X-ray spectroscopy and density functional theory to show that the electronic structure of LaNiO 2 and NdNiO 2 , while similar to the cuprates, includes significant distinctions. Unlike cuprates, the rare-earth spacer layer in the infinite-layer nickelate supports a weakly interacting three-dimensional 5 d metallic state, which hybridizes with a quasi-two-dimensional, strongly correlated state with 3 d x 2 − y 2 symmetry in the NiO 2 layers. Thus, the infinite-layer nickelate can be regarded as a sibling of the rare-earth intermetallics 13 – 15 , which are well known for heavy fermion behaviour, where the NiO 2 correlated layers play an analogous role to the 4 f states in rare-earth heavy fermion compounds. This Kondo- or Anderson-lattice-like ‘oxide-intermetallic’ replaces the Mott insulator as the reference state from which superconductivity emerges upon doping. X-ray spectroscopy and density functional theory are used to show that the electronic structure of the parent compound of superconducting infinite-layer nickelates, while similar to the copper-based high-temperature superconductors, has significant differences.

• Publisher: Nature Publishing Group UK,Nature Publishing Group,Springer Nature - Nature Publishing Group
• Subject: 639/301 / 639/766 / Biomaterials / Chemistry and Materials Science / Condensed Matter Physics / CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY / Copper compounds / Cuprates / Density functional theory / Earth / Electronic properties / Electronic structure / Electrons / Fermions / High temperature / High temperature superconductors / Letter / Materials Science / Nanotechnology / Nickel / Optical and Electronic Materials / Physics / Rare earth elements / Spectrum analysis / Superconductivity / X-ray spectroscopy