Observation of Discrete Conventional Caroli-de Gennes-Matricon States in the Vortex Core of Single-Layer FeSe/SrTiO3

被引：34
作者：
Chen, Chen [1 ,2 ,6 ]
Liu, Qin [1 ,2 ,3 ,6 ]
Bao, Wei-Cheng [4 ,5 ,9 ]
Yan, Yajun [1 ,2 ,6 ]
Wang, Qiang-Hua [4 ,5 ,6 ]
Zhang, Tong [1 ,2 ,6 ]
Feng, Donglai [1 ,2 ,6 ,7 ,8 ]
机构：
[1] Fudan Univ, Dept Phys, State Key Lab Surface Phys, Shanghai 200438, Peoples R China
[2] Fudan Univ, Adv Mat Lab, Shanghai 200438, Peoples R China
[3] Sci & Technol Surface Phys & Chem Lab, Mianyang 621908, Sichuan, Peoples R China
[4] Nanjing Univ, Natl Lab Solid State Microstruct, Nanjing 210093, Peoples R China
[5] Nanjing Univ, Sch Phys, Nanjing 210093, Peoples R China
[6] Collaborat Innovat Ctr Adv Microstruct, Nanjing 210093, Peoples R China
[7] Univ Sci & Technol China, Hefei Natl Lab Phys Sci Microscale, Hefei 230026, Anhui, Peoples R China
[8] Univ Sci & Technol China, Dept Phys, Hefei 230026, Anhui, Peoples R China
[9] Zhejiang Univ Water Resources & Elect Power, Hangzhou 310018, Peoples R China
来源：
PHYSICAL REVIEW LETTERS | 2020年 / 124卷 / 09期
基金：
中国国家自然科学基金;
关键词：
SUPERCONDUCTIVITY;
D O I：
10.1103/PhysRevLett.124.097001
中图分类号：
O4 [物理学];
学科分类号：
0702 ;
摘要：
Using low-temperature scanning tunneling microscopy (STM), we studied the vortex states of single-layer FeSe film on a SrTiO3 (100) substrate, and the local behaviors of superconductivity at sample boundaries. We clearly observed multiple discrete Caroli-de Gennes-Matricon states in the vortex core, and quantitative analysis shows their energies well follow the formula: E/ mu Delta(2)/E-F, where mu is a half integer (+/- 1/2, +/- 3/2, +/- 5/2.) and. is the mean superconducting gap over the Fermi surface. Meanwhile, a fully gapped spectrum without states near zero bias is observed at the [110](Fe) oriented boundary of 1 and 2 ML FeSe films, and atomic step edge of 1 ML FeSe. Accompanied with theoretical calculations, our results indicate an s-wave pairing without sign change in the high-T-C FeSe/SrTiO3 superconductor.
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页数：6
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