摘要
Iron-based superconductor family FeX(X=S,Se,Te)has been one of the research foci in physics and material science due to their record-breaking superconducting temperature(FeSe film)and rich physical phenomena.Recently,FeS,the least studied Fe X compound(due to the difficulty in synthesizing high quality macroscopic crystals)attracted much attention because of its puzzling superconducting pairing symmetry.In this work,combining scanning tunneling microscopy and angle resolved photoemission spectroscopy(ARPES)with sub-micron spatial resolution,we investigate the intrinsic electronic structures of superconducting FeS from individual single crystalline domains.Unlike FeTe or FeSe,FeS remains identical tetragonal structure from room temperature down to 5 K,and the band structures observed can be well reproduced by our ab-initio calculations.Remarkably,mixed with the 1×1 tetragonal metallic phase,we also observe the coexistence of √5×√5 reconstructed insulating phase in the crystal,which not only helps explain the unusual properties of FeS,but also demonstrates the importance of using spatially resolved experimental tools in the study of this compound.
作者
王成玮
王美晓
姜娟
杨海峰
杨乐仙
史武军
赖晓芳
Sung-Kwan Mo
Alexei Barinov
颜丙海
刘志
黄富强
贾金峰
柳仲楷
陈宇林
Chengwei Wang;Meixiao Wang;Juan Jiang;Haifeng Yang;Lexian Yang;Wujun Shi;Xiaofang Lai;Sung-Kwan Mo;Alexei Barinov;Binghai Yan;Zhi Liu;Fuqiang Huang;Jinfeng Jia;Zhongkai Liu;Yulin Chen(State Key Laboratory of Functional Materials for Informatics,Shanghai Institute of Microsystem and Information Technology(SIMIT),Chinese Academy of Sciences,Shanghai 200050,China;School of Physical Science and Technology,ShanghaiTech University,CAS-Shanghai Science Research Center,Shanghai 200031,China;University of Chinese Academic of Sciences,Beijing 100049,China;Advanced Light Source,Lawrence Berkeley National Laboratory,Berkeley,CA 94720,USA;State Key Laboratory of Low Dimensional Quantum Physics,Department of Physics and Collaborative Innovation Center for Quantum Matter,Tsinghua University,Beijing 100084,China;Beijing National Laboratory for Molecular Sciences and State Key Laboratory of Rare Earth Materials Chemistry and Applications,College of Chemistry and Molecular Engineering,Peking University,Beijing 100871,China;Elettra-Sincrotrone Trieste ScPA,Trieste,Basovizza 34149,Italy;Max Planck Institute for Chemical Physics of Solids,D-01187 Dresden,Germany;State Key Laboratory of High Performance Ceramics and Superfine Microstructure,Shanghai Institute of Ceramics,Chinese Academy of Sciences,Shanghai 200050,China;Key Laboratory of Artificial Structures and Quantum Control(Ministry of Education),Department of Physics and Astronomy,Shanghai Jiao Tong University,Shanghai 200240,China;Physics Department,Oxford University,Oxford,OX13PU,UK)
基金
Project supported by CAS-Shanghai Science Research Center,China(Grant No.CAS-SSRC-YH-2015-01)
the National Key R&D Program of China(Grant No.2017YFA0305400)
the National Natural Science Foundation of China(Grant Nos.11674229,11227902,and 11604207)
the EPSRC Platform Grant(Grant No.EP/M020517/1)
Hefei Science Center,Chinese Academy of Sciences(Grant No.2015HSC-UE013)
Science and Technology Commission of Shanghai Municipality,China(Grant No.14520722100)
the Strategic Priority Research Program(B)of the Chinese Academy of Sciences(Grant No.XDB04040200)。