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

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.

arXiv comment4 pages, 4 figures

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