Electric-field-controlled superconductor-ferromagnetic insulator transition

Likuan Ma; Bin Lei; Naizhou Wang; Kaishuai Yang; Dayong Liu; Fanbao Meng; Chao Shang; Zeliang Sun; Jianhua Cui; Changsheng Zhu; Tao Wu; Zhe Sun; Liangjian Zou; Xianhui Chen

doi:10.1016/j.scib.2019.04.022

Electric-field-controlled superconductor-ferromagnetic insulator transition

Sci Bull (Beijing). 2019 May 30;64(10):653-658. doi: 10.1016/j.scib.2019.04.022. Epub 2019 Apr 18.

Authors

Likuan Ma¹, Bin Lei¹, Naizhou Wang¹, Kaishuai Yang², Dayong Liu², Fanbao Meng¹, Chao Shang¹, Zeliang Sun¹, Jianhua Cui¹, Changsheng Zhu¹, Tao Wu³, Zhe Sun⁴, Liangjian Zou², Xianhui Chen⁵

Affiliations

¹ Hefei National Laboratory for Physical Sciences at Microscale and Department of Physics, and CAS Key Laboratory of Strongly-coupled Quantum Matter Physics, University of Science and Technology of China, Hefei 230026, China.
² Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, China.
³ Hefei National Laboratory for Physical Sciences at Microscale and Department of Physics, and CAS Key Laboratory of Strongly-coupled Quantum Matter Physics, University of Science and Technology of China, Hefei 230026, China; CAS Center for Excellence in Quantum Information and Quantum Physics, Hefei 230026, China; Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China.
⁴ National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230026, China; Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China.
⁵ Hefei National Laboratory for Physical Sciences at Microscale and Department of Physics, and CAS Key Laboratory of Strongly-coupled Quantum Matter Physics, University of Science and Technology of China, Hefei 230026, China; CAS Center for Excellence in Quantum Information and Quantum Physics, Hefei 230026, China; Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China; CAS Center for Excellence in Superconducting Electronics (CENSE), Shanghai 200050, China. Electronic address: chenxh@ustc.edu.cn.

PMID: 36659647
DOI: 10.1016/j.scib.2019.04.022

Abstract

Superconductivity beyond electron-phonon mechanism is always twisted with magnetism. Based on a new field-effect transistor with solid ion conductor as the gate dielectric (SIC-FET), we successfully achieve an electric-field-controlled phase transition between superconductor and ferromagnetic insulator in (Li,Fe)OHFeSe. A dome-shaped superconducting phase with optimal T_c of 43 K is continuously tuned into a ferromagnetic insulating phase, which exhibits an electric-field-controlled quantum critical behavior. The origin of the ferromagnetism is ascribed to the order of the interstitial Fe ions expelled from the (Li,Fe)OH layers by gating-controlled Li injection. These surprising findings offer a unique platform to study the relationship between superconductivity and ferromagnetism in Fe-based superconductors. This work also demonstrates the superior performance of the SIC-FET in regulating physical properties of layered unconventional superconductors.

Keywords: FeSe-based superconductors; Ferromagnetic insulator; Phase transition; Solid ion conductor field-effect transistors (SIC-FET).