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arXiv · 1905.06901

Coexistence of ferromagnetic fluctuations and superconductivity in the actinide superconductor UTe2

Shyam Sundar·S. Gheidi·K. Akintola·A. M. Cote·S. R. Dunsiger·S. Ran·N. P. Butch·S. R. Saha·J. Paglione·J. E. Sonier
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Abstract

We report low-temperature muon spin relaxation/rotation (muSR) measurements on single crystals of the actinide superconductor UTe2. Below 5 K we observe a continuous slowing down of magnetic fluctuations that persists through the superconducting (SC) transition temperature (Tc = 1.6 K), but we find no evidence of long-range or local magnetic order down to 0.025 K. The temperature dependence of the dynamic relaxation rate down to 0.4 K agrees with the self-consistent renormalization theory of spin fluctuations for a three-dimensional weak itinerant ferromagnetic metal. Our muSR measurements also indicate that the superconductivity coexists with the magnetic fluctuations.

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Shyam Sundar, S. Gheidi, K. Akintola, A. M. Cote, S. R. Dunsiger, S. Ran, N. P. Butch, S. R. Saha, J. Paglione, J. E. Sonier. 2019-08-20. Coexistence of ferromagnetic fluctuations and superconductivity in the actinide superconductor UTe2. https://doi.org/10.1103/physrevb.100.140502

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