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(13)C NMR investigation of the superconductor MgCNi_3 up to 800K

P. M. Singer·T. Imai·T. He·M. A. Hayward·R. J. Cava
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Abstract

We report (13)C NMR characterization of the new superconductor MgCNi_3 (He et al., Nature (411), 54 (2001)). We found that both the uniform spin susceptibility and the spin fluctuations show a strong enhancement with decreasing temperature, and saturate below ~50K and ~20K respectively. The nuclear spin-lattice relaxation rate 1/(13)T_1T exhibits typical behaviour for isotropic s-wave superconductivity with a coherence peak below Tc=7.0K that grows with decreasing magnetic field.

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P. M. Singer, T. Imai, T. He, M. A. Hayward, R. J. Cava. 2001-11-01. (13)C NMR investigation of the superconductor MgCNi_3 up to 800K. https://doi.org/10.1103/physrevlett.87.257601

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