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Comment on "Experimental determination of superconducting parameters for the intermetallic perovskite superconductor MgCNi$_3$"

Yu. G. Naidyuk
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Abstract

In a recent paper (Phys. Rev. {\bf B 67}, 094502 (2003)) Mao et al. investigated the bias-dependent conductance of mechanical junctions between superconducting MgCNi$_3$ and a sharp W tip. They interpreted their results in terms of 'single-particle tunneling'. We show it is more likely that current transport through those junctions is determined by thermal effects due to the huge normal-state resistivity of MgCNi$_3$. Therefore no conclusion can be drawn about the possible unconventional pairing or strong-coupling superconductivity in MgCNi$_3$.

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Yu. G. Naidyuk. 2003-12-16. Comment on "Experimental determination of superconducting parameters for the intermetallic perovskite superconductor MgCNi$_3$". https://doi.org/10.1103/physrevb.69.136501

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