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.
Cite
@article{arxiv.cond-mat/0410504,
title = {Carbon isotope effect in superconducting MgCNi_3},
author = {T. Klimczuk and R. J. Cava},
journal= {arXiv preprint arXiv:cond-mat/0410504},
year = {2009}
}
Comments
To be published in Phys. Rev. B. 4 pages, 1 figure