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arXiv · 0901.0177

75As NMR Study of Hole-Doped Superconductor Ba1-xKxFe2As2 (Tc = 38K)

H. Fukazawa·T. Yamazaki·K. Kondo·Y. Kohori·N. Takeshita·P. M. Shirage·K Kihou·K. Miyazawa·H. Kito·H. Eisaki·A. Iyo
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Abstract

We report the 75As nuclear magnetic resonance (NMR) measurement of the hole-doped superconductor Ba1-xKxFe2As2 with different lattice parameters and different superconducting volume fractions (Tc = 38K). 75As-NMR spectra revealed that the magnetically ordered and superconducting phases are microscopically separated. The spin-lattice relaxation rate 1/T1 in the normal state reflects the existence of a large two-dimensional antiferromagnetic spin fluctuation. The 1/T1 in the superconducting state down to the lowest measurement temperature T varies close to T^3. In addition, it exhibits no coherence peak just below Tc. This shows a T dependence similar to those of other iron pnictides.

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H. Fukazawa, T. Yamazaki, K. Kondo, Y. Kohori, N. Takeshita, P. M. Shirage, K Kihou, K. Miyazawa, H. Kito, H. Eisaki, A. Iyo. 2009-02-02. 75As NMR Study of Hole-Doped Superconductor Ba1-xKxFe2As2 (Tc = 38K). https://doi.org/10.1143/jpsj.78.033704

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