Strain-mediated insulator-metal transition in topotactically hydro-reduced SrFeO_(2)  

作　　者：Shuang Chen Jiali Zhao Qiao Jin Shan Lin Shengru Chen Hongbao Yao Jiaou Wang Zhen Fan Er-Jia Guo Haizhong Guo 

机构地区：[1]School of Physics and Microelectronics,Zhengzhou University,Zhengzhou 450001,China [2]Beijing National Laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China [3]School of Physical Sciences,University of Chinese Academy of Sciences,Beijing 100049,China [4]Institute of High Energy Physics,Chinese Academy of Sciences,Beijing 100049,China [5]Institute for Advanced Materials and Guangdong Provincial Key Laboratory of Optical Information Materials and Technology,South China Academy of Advanced Optoelectronics,South China Normal University,Guangzhou 510006,China [6]Songshan Lake Materials Laboratory,Dongguan 523808,China [7]Center of Materials Science and Optoelectronics Engineering,University of Chinese Academy of Sciences,Beijing 100049,China [8]Collaborative Innovation Center of Light Manipulations and Applications,Shandong Normal University,Jinan 250358,China

出　　处：《Science China(Physics,Mechanics & Astronomy)》2021年第8期114-119,共6页中国科学：物理学、力学、天文学（英文版）

基　　金：supported by the National Key Basic Research Program of China(Grant Nos.2020YFA0309100,and 2019YFA0308500);the Program for the Innovation Team of Science and Technology in University of Henan(Grant No.20IRTSTHN014);the Excellent Youth Foundation of He’nan Scientific Committee(Grant No.202300410356);the National Natural Science Foundation of China(Grant No.11974390);the Beijing Nova Program of Science and Technology(Grant No.Z191100001119112);the Beijing Natural Science Foundation(Grant No.2202060);the Strategic Priority Research Program(B)of the Chinese Academy of Sciences(Grant No.XDB33030200)。

摘　　要：Controlling oxygen redox reactions in transition metal oxides offers an attractive route to tune their physical properties;a topotactic structural transformation from their parent phases effectively modifies the electronic state. In this work, infinitelayered SrFeO_(2) thin films were produced from brownmillerite SrFeO_(2.5) via low-temperature hydro-reduction. After the structural transition, their out-of-plane lattice constants dramatically shrank by 12%;tensilely strained samples exhibited metallic character, whereas the compressively strained ones maintained the insulating behavior of their bulk form. According to X-ray linear dichroism results, this strain-mediated electronic anisotropy may be attributed to electron redistribution within degenerated orbitals. This suggests a possible mechanism for the metallic conductivity of infinite-layered SrFeO_(2), giving a hint for understanding emergent quantum phenomena, such as the recently discovered superconductivity in nickelates, and stimulating various applications, including in ionic conductivity and oxygen catalysis.

关 键 词：FERRITE HYDROGENATION insulator-metal transition infinite layers electronic states 

分 类 号：O469[理学—凝聚态物理]