Superconducting gap structure of FeSe

被引:45
作者
Jiao, Lin [1 ]
Huang, Chien-Lung [1 ,3 ]
Roessler, Sahana [1 ]
Koz, Cevriye [1 ]
Roessler, Ulrich K. [2 ]
Schwarz, Ulrich [1 ]
Wirth, Steffen [1 ]
机构
[1] Max Planck Inst Chem Phys Solids, Nothnitzer Str 40, D-01187 Dresden, Germany
[2] IFW Dresden, Postfach 270016, D-01171 Dresden, Germany
[3] Rice Univ, Dept Phys & Astron, Houston, TX 77005 USA
关键词
TEMPERATURE; SYMMETRY; PHASE; FILMS;
D O I
10.1038/srep44024
中图分类号
O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];
学科分类号
07 ; 0710 ; 09 ;
摘要
The microscopic mechanism governing the zero-resistance flow of current in some iron-based, high-temperature superconducting materials is not well understood up to now. A central issue concerning the investigation of these materials is their superconducting gap symmetry and structure. Here we present a combined study of low-temperature specific heat and scanning tunnelling microscopy measurements on single crystalline FeSe. The results reveal the existence of at least two superconducting gaps which can be represented by a phenomenological two-band model. The analysis of the specific heat suggests significant anisotropy in the gap magnitude with deep gap minima. The tunneling spectra display an overall "U"-shaped gap close to the Fermi level away as well as on top of twin boundaries. These results are compatible with the anisotropic nodeless models describing superconductivity in FeSe.
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页数:8
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