Strong nodeless pairing on separate electron Fermi surface sheets in (Tl, K)Fe1.78Se2 probed by ARPES

被引：130

作者：

Wang, X. -P. ^{[1
,2
]}

Qian, T. ^{[1
,2
]}

Richard, P. ^{[1
,2
]}

Zhang, P. ^{[1
,2
]}

Dong, J. ^{[1
,2
]}

Wang, H. -D. ^{[3
]}

Dong, C. -H. ^{[3
]}

Fang, M. -H. ^{[3
]}

Ding, H. ^{[1
,2
]}

机构：

[1] Chinese Acad Sci, Beijing Natl Lab Condensed Matter Phys, Beijing 100190, Peoples R China

[2] Chinese Acad Sci, Inst Phys, Beijing 100190, Peoples R China

[3] Zhejiang Univ, Dept Phys, Hangzhou 310027, Zhejiang, Peoples R China

来源：

EPL | 2011年 / 93卷 / 05期

关键词：

RESOLVED PHOTOEMISSION-SPECTROSCOPY; SUPERCONDUCTING GAPS; BA0.6K0.4FE2AS2;

D O I：

10.1209/0295-5075/93/57001

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

We performed a high-resolution angle-resolved photoemission spectroscopy study of the Tl0.63K0.37Fe1.78Se2 superconductor (T-c = 29 K). We show the existence of two electron-like bands at the M(pi, 0)-point which cross the Fermi level at similar Fermi wave vectors to form nearly circular electron-like Fermi surface pockets. We observe a nearly isotropic similar to 8.5meV superconducting gap (2 Delta/k(B)T(c) similar to 7) on these Fermi surfaces. Our analysis of the band structure around the Brillouin zone centre reveals two additional electron-like Fermi surfaces: a very small one and a larger one with k(F) comparable to the Fermi surfaces at M. Interestingly, a superconducting gap with a magnitude of similar to 8meV also develops along the latter Fermi surface. Our observations are consistent with the s-wave strong-coupling scenario. Copyright (c) EPLA, 2011

引用

页数：4

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