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arXiv · 1205.0787

Angle-resolved photoemission evidence of s-wave superconducting gap in KxFe2-ySe2 superconductor

M. Xu·Q. Q. Ge·R. Peng·Z. R. Ye·Juan Jiang·F. Chen·X. P. Shen·B. P. Xie·Y. Zhang·D. L. Feng
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Abstract

Although nodeless superconducting gap has been observed on the large Fermi pockets around the zone corner in KxFe2-ySe2, whether its pairing symmetry is s-wave or nodeless d-wave is still under intense debate. Here we report an isotropic superconducting gap distribution on the small electron Fermi pocket around the Z point in KxFe2-ySe2, which favors the s-wave pairing symmetry.

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M. Xu, Q. Q. Ge, R. Peng, Z. R. Ye, Juan Jiang, F. Chen, X. P. Shen, B. P. Xie, Y. Zhang, D. L. Feng. 2012-05-03. Angle-resolved photoemission evidence of s-wave superconducting gap in KxFe2-ySe2 superconductor. https://doi.org/10.1103/physrevb.85.220504

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