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arXiv · 0904.1571

75As NMR Observation of Anisotropic Spin Fluctuations in the Ba[(Fe0.92Co0.08)2]2As2 Superconductor (Tc = 22 K)

Fanlong Ning·Kanagasingham Ahilan·Takashi Imai·Athena S Sefat·Rongying Jin·Michael A. McGuire·Brian C Sales·David Mandrus
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Abstract

We demonstrate that the anisotropy R of the paramagnetic spin fluctuations grows toward Tc at 75As sites in the optimally electron-doped superconductor Ba[(Fe0.92Co0.08)2]2As2, with stronger spin fluctuations along the c-axis. Our finding is in remarkable contrast with the case of high T$_c$ cuprates, where R is independent of temperature above Tc.

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Fanlong Ning, Kanagasingham Ahilan, Takashi Imai, Athena S Sefat, Rongying Jin, Michael A. McGuire, Brian C Sales, David Mandrus. 2009-04-09. 75As NMR Observation of Anisotropic Spin Fluctuations in the Ba[(Fe0.92Co0.08)2]2As2 Superconductor (Tc = 22 K). https://arxiv.org/abs/0904.1571

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