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arXiv · 1101.1017

77Se NMR study of pairing symmetry and spin dynamics in KyFe2-xSe2

Weiqiang Yu·L. Ma·J. B. He·D. M. Wang·T. -L. Xia·G. F. Chen·Wei Bao
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Abstract

We present a 77Se NMR study of the newly discovered iron selenide superconductor KyFe2-xSe2, in which Tc = 32 K. Below Tc, the Knight shift 77K drops sharply with temperature, providing strong evidence for singlet pairing. Above Tc, Korringa-type relaxation indicates Fermi-liquid behavior. Our experimental results set strict constraints on the nature of possible theories for the mechanism of high-Tc superconductivity in this iron selenide system.

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Weiqiang Yu, L. Ma, J. B. He, D. M. Wang, T. -L. Xia, G. F. Chen, Wei Bao. 2011-04-13. 77Se NMR study of pairing symmetry and spin dynamics in KyFe2-xSe2. https://doi.org/10.1103/physrevlett.106.197001

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