Superconductivity in an infinite-layer nickelate superlattice

Wen Xiao; Zhan Yang; Shilin Hu; Yuzhou He; Xiaofei Gao; Junhua Liu; Zhixiong Deng; Yuhao Hong; Long Wei; Lei Wang; Ziyue Shen; Tianyang Wang; Lin Li; Yulin Gan; Kai Chen; Qinghua Zhang; Zhaoliang Liao

doi:10.1038/s41467-024-54660-w

Superconductivity in an infinite-layer nickelate superlattice

Nat Commun. 2024 Nov 25;15(1):10215. doi: 10.1038/s41467-024-54660-w.

Authors

Wen Xiao¹, Zhan Yang^{1

2}, Shilin Hu¹, Yuzhou He³, Xiaofei Gao¹, Junhua Liu¹, Zhixiong Deng¹, Yuhao Hong¹, Long Wei¹, Lei Wang¹, Ziyue Shen¹, Tianyang Wang¹, Lin Li¹, Yulin Gan⁴, Kai Chen⁵, Qinghua Zhang⁶, Zhaoliang Liao⁷

Affiliations

¹ National Synchrotron Radiation Laboratory, School of Nuclear Science and Technology, University of Science and Technology of China, Hefei, China.
² School of Physics, Zhengzhou University, Zhengzhou, China.
³ Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China.
⁴ National Synchrotron Radiation Laboratory, School of Nuclear Science and Technology, University of Science and Technology of China, Hefei, China. ylgan@ustc.edu.cn.
⁵ National Synchrotron Radiation Laboratory, School of Nuclear Science and Technology, University of Science and Technology of China, Hefei, China. kaichen2021@ustc.edu.cn.
⁶ Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China. zqh@iphy.ac.cn.
⁷ National Synchrotron Radiation Laboratory, School of Nuclear Science and Technology, University of Science and Technology of China, Hefei, China. zliao@ustc.edu.cn.

Abstract

Recent observations of superconductivity in infinite-layer nickelates offer insights into high-temperature superconductivity mechanisms. However, defects and dislocations in doped films complicate the realization of superconductivity, limiting current research to superconducting nickelate heterostructures. The lack of research on superconductivity in superlattices composed of ultrathin nickelates severely impedes not only the exploration of the interface effect on superconductivity, but also the utilization of heterostructure engineering for exploring higher superconducting temperature T_c. Here, we demonstrated superconducting infinite-layer nickelate superlattices [(Nd_0.8Sr_0.2NiO₂)₈/(SrTiO₃)₂]₁₀ via topotactic reduction. Our study uncovered that only above a critical thickness can high-quality superlattices be achieved, with structural formation dependent on nickelate layer thickness. The superconducting superlattice showed a T_c of 12.5 K and a 2D superconducting feature, indirectly indicate the intrinsic superconductivity of infinite-layer nickelates. Our study offers promising avenues for delving into the superconducting mechanism and for exploring multilevel interface engineering of infinite-layer nickelates, thus opening new horizons for the study of infinite-layer nickelates.