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Title: Nickelate Superconductivity without Rare‐Earth Magnetism: (La,Sr)NiO 2
Abstract

The occurrence of unconventional superconductivity in cuprates has long motivated the search for manifestations in other layered transition metal oxides. Recently, superconductivity is found in infinite‐layer nickelate (Nd,Sr)NiO2and (Pr,Sr)NiO2thin films, formed by topotactic reduction from the perovskite precursor phase. A topic of much current interest is whether rare‐earth moments are essential for superconductivity in this system. In this study, it is found that with significant materials optimization, substantial portions of the La1−xSrxNiO2phase diagram can enter the regime of coherent low‐temperature transport (x = 0.14 ‐ 0.20), with subsequent superconducting transitions and a maximum onset of ≈9 K atx = 0.20. Additionally, the unexpected indication of a superconducting ground state in undoped LaNiO2is observed, which likely reflects the self‐doped nature of the electronic structure. Combining the results of (La/Pr/Nd)1−xSrxNiO2reveals a generalized superconducting dome, characterized by systematic shifts in the unit cell volume and in the relative electron‐hole populations across the lanthanides.

 
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Award ID(s):
1719875
NSF-PAR ID:
10360059
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Materials
Volume:
33
Issue:
45
ISSN:
0935-9648
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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