NMR investigation on the high-field superconducting phases of UTe<sub>2</sub> in fields along the hard magnetic axis

ORAL

Abstract

The unconventional superconductor UTe2 is known to exhibit a sequence of field-induced phases in the presence of magnetic field (Bb) aligned with the hard magnetic axis (b-axis). At relatively low field (Bb < 14 T), its properties are interpreted as consistent with a triplet-paired superconducting (SC) ground state (dubbed low-field SC or LFSC phase) [1]. At higher field a different high-field SC phase (HFSC) is stabilized, for which the symmetry is still debated. Recently, a molten-salt-flux technique has led to an improved single crystal quality, with the zero-field SC critical temperature reaching Tc = 2.1 K. These higher-quality crystals are reported to host an intermediate-field SC phase (IFSC) [2]; to date, the properties of the IFSC phase remain largely unexplored. Here, we report the results of 125Te nuclear magnetic resonance (NMR) measurements, performed in the normal and SC states on a UTe2 single crystal grown by the molten-salt-flux technique, in magnetic fields up to Bb = 30 T. Our observations suggest that the normal and SC state properties may greatly depend on the crystal quality and growth techniques.



[1] H. Matsumura et al, J. Phys. Soc. Jpn. 92, 063701 (2023).

[2] H. Sakai et al, Phys. Rev. Lett. 130, 196002 (2023).

*USDOE Office of Science (SC). Office of Basic Energy Sciences (BES)(SC-32), and National Science Foundation grant no. 2004553. Work at the National High Magnetic Field Laboratory is supported by NSF Cooperative Agreement Number DMR- 2128556 and by the State of Florida.

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Presenters

  • Riku Yamamoto

    • Los Alamos National Laboratory

Authors

  • Riku Yamamoto

    • Los Alamos National Laboratory

  • Phurba Sherpa

    • University of California, Davis

  • Austin J Baker

    • University of California, Los Angeles

  • Xiaoling Wang

    • FSU-NHMFL

  • Mitchell Bordelon

    • Los Alamos National Laboratory

  • Priscila Rosa

    • Los Alamos National Laboratory

  • Adam P Dioguardi

    • Los Alamos National Laboratory
    • Los Alamos National Labs

  • Sean M Thomas

    • Los Alamos National Laboratory
    • Los Alamos National Laboratory, Los Alamos, NM87545, USA

  • Filip Ronning

    • Los Alamos National Laboratory

  • Joe D Thompson

    • Los Alamos Natl Lab

  • Eric D Bauer

    • Los Alamos Natl Lab
    • Los Alamos National Laboratory (LANL)

  • Stuart E Brown

    • University of California, Los Angeles

  • Arneil P Reyes

    • FSU-NHMFL

  • Michihiro Hirata

    • Los Alamos National Laboratory