Synthesis of Chemically Sharp Interface in NdNiO_(3)/SrTiO_(3) Heterostructures  

作　　者：李月莹 蔡祥滨 孙文杰 杨江枫 郭维 顾正彬 朱叶 聂越峰 Yueying Li;Xiangbin Cai;Wenjie Sun;Jiangfeng Yang;Wei Guo;Zhengbin Gu;Ye Zhu;Yuefeng Nie(National Laboratory of Solid State Microstructures,Jiangsu Key Laboratory of Artificial Functional Materials,College of Engineering and Applied Sciences,Nanjing University,Nanjing 210093,China;Collaborative Innovation Center of Advanced Microstructures,Nanjing University,Nanjing 210093,China;Department of Applied Physics,Research Institute for Smart Energy,The Hong Kong Polytechnic University,Hong Kong 999077,China)

机构地区：[1]National Laboratory of Solid State Microstructures,Jiangsu Key Laboratory of Artificial Functional Materials,College of Engineering and Applied Sciences,Nanjing University,Nanjing 210093,China [2]Collaborative Innovation Center of Advanced Microstructures,Nanjing University,Nanjing 210093,China [3]Department of Applied Physics,Research Institute for Smart Energy,The Hong Kong Polytechnic University,Hong Kong 999077,China

出　　处：《Chinese Physics Letters》2023年第7期45-50,共6页中国物理快报（英文版）

基　　金：supported by the National Key Projects for Research and Development of China(Grant No.2022YFA1402502 and 2021YFA1400400);the National Natural Science Foundation of China(Grant No.11861161004);the Fundamental Research Funds for the Central Universities(Grant No.0213–14380221);the Research Grants Council of Hong Kong(Grant No.N PolyU531/18);the Hong Kong Polytechnic University(Grant No.ZVRP)。

摘　　要：The nickel-based superconductivity provides a fascinating new platform to explore high-Tc superconductivity.As the infinite-layer nickelates are obtained by removing the apical oxygens from the precursor perovskite phase,the crystalline quality of the perovskite phase is crucial in synthesizing high quality superconducting nickelates.Especially,cation-related defects,such as the Ruddlesden–Popper-type(RP-type)faults,are unlikely to disappear after the topotactic reduction process and should be avoided during the growth of the perovskite phase.Herein,using reactive molecular beam epitaxy,we report the atomic-scale engineering of the interface structure and demonstrate its impact in reducing crystalline defects in Nd-based nickelate/SrTiO_(3) heterostructures.A simultaneous deposition of stoichiometric Nd and Ni directly on SrTiO_(3) substrates results in prominent Nd vacancies and Ti diffusion at the interface and RP-type defects in nickelate films.In contrast,inserting an extra[NdO]monolayer before the simultaneous deposition of Nd and Ni forms a sharp interface and greatly eliminates RP-type defects in nickelate films.A possible explanation related to the polar discontinuity is also discussed.Our results provide an effective method to synthesize high-quality precursor perovskite phase for the investigation of the novel superconductivity in nickelates.

关 键 词：PEROVSKITE SUPERCONDUCTIVITY NICKEL 

分 类 号：O511[理学—低温物理] TB34[理学—物理]