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Magnetic quantum critical point and superconductivity in UPt3 doped with Pd

A. de Visser·M. J. Graf·P. Estrela·A. Amato·C. Baines·D. Andreica·F. N. Gygax·A. Schenck
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Abstract

Transverse-field muon spin relaxation measurements have been carried out on the heavy-fermion superconductor UPt3 doped with small amounts of Pd. We find that the critical Pd concentration for the emergence of the large-moment antiferromagnetic phase is ~0.6 at.%Pd. At the same Pd content, superconductivity is completely suppressed. The existence of a magnetic quantum critical point in the phase diagram, which coincides with the critical point for superconductivity, provides evidence for ferromagnetic spin-fluctuation mediated odd-parity superconductivity, which competes with antiferromagnetic order.

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A. de Visser, M. J. Graf, P. Estrela, A. Amato, C. Baines, D. Andreica, F. N. Gygax, A. Schenck. 2000-10-02. Magnetic quantum critical point and superconductivity in UPt3 doped with Pd. https://doi.org/10.1103/physrevlett.85.3005

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