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Evidence for Unconventional Superconductivity in the Non-Oxide Perovskite $\mathrm{MgCNi_3}$ from Penetration Depth Measurements

R. Prozorov·A. Snezhko·T. He·R. J. Cava
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Abstract

The London penetration depth, $λ(T)$, was measured in polycrystalline powders of the non-oxide perovskite superconductor $\mathrm{MgCNi_3}$ by using a sensitive tunnel-diode resonator technique. The penetration depth exhibits distinctly non s-wave BCS low-temperature behavior, instead showing quadratic temperature dependence, suggestive of a nodal order parameter.

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R. Prozorov, A. Snezhko, T. He, R. J. Cava. 2003-02-21. Evidence for Unconventional Superconductivity in the Non-Oxide Perovskite $\mathrm{MgCNi_3}$ from Penetration Depth Measurements. https://doi.org/10.1103/physrevb.68.180502

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