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The Effect of Ru substitution for Ni on the superconductivity in MgCNi3-xRux

T. Klimczuk·V. Gupta·G. Lawes·A. P. Ramirez·R. J. Cava
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Abstract

The superconductor MgCNi3 has been chemically doped by partial substitution of Ru for Ni in the solid solution MgCNi3-xRux for 0<x<0.5. Magnetic and specific heat measurements show that the Sommerfeld parameter (gamma_exp) and TC decrease immediately on Ru substitution, but that a TC above 2K is maintained even for a relatively large decrease in gamma_exp. Ferromagnetism is not observed to develop through Ru substitution, and the normal state magnetic susceptibility is suppressed.

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T. Klimczuk, V. Gupta, G. Lawes, A. P. Ramirez, R. J. Cava. 2004-06-17. The Effect of Ru substitution for Ni on the superconductivity in MgCNi3-xRux. https://doi.org/10.1103/physrevb.70.094511

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