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Carbon isotope effect in superconducting MgCNi_3

T. Klimczuk·R. J. Cava
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Abstract

The effect of Carbon isotope substitution on T_c in the intermetallic perovskite superconductor MgCNi_3 is reported. Four independent groups of samples were synthesized and characterized. The average T_c for the Carbon-12 samples was found to be 7.12(2) K and the average T_c for the Carbon-13 samples was found to be 6.82(2) K. The resulting carbon isotope effect coefficient is alfa_C = 0.54(3). This indicates that carbon-based phonons play a critical role in the presence of superconductivity in this compound.

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T. Klimczuk, R. J. Cava. 2004-10-20. Carbon isotope effect in superconducting MgCNi_3. https://doi.org/10.1103/physrevb.70.212514

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