Field-induced Pseudogap in the Heavy-fermion Superconductor CeCoIn<sub>5</sub>

ORAL

Abstract

The heavy-fermion superconductor CeCoIn5, whose order parameter is known to have dx2-y2 symmetry [1], manifests an interesting spin density wave-like Q-phase [2]. Despite several recent scanning tunneling spectroscopic measurements [3], there are no phase-sensitive measurements in the Q-phase. Our planer tunneling spectroscopy data at 20 mK show sharp coherence peaks and the estimated gap size is 0.65 meV. Quite intriguingly, the superconducting gap-like features evolve into a pseudogap as superconductivity is destroyed with temperature and magnetic fields. The field-induced pseudogap is enhanced further with increasing fields up to the highest measurements field of 18 T. The possible origin of the pseudogap and implications of our results will be discussed.

[1]J. D. Thompson et al.,JPSJ 81, 011002 (2012); W.K. Park, et al. PRL 100, 177001 (2008).
[2]M. Kenzelmann, et al.,Science, 321, 1652 (2008).
[3]Y. Fasano, et al.,Physica B 536, 798 (2018); A. Gyenis, et al.,Nat. Commun. 9, 549 (2018); M. P. Allan, et al.,Nat. Phys. 9, 468 (2013); B. B. Zhou, et al.,Nat. Phys. 9, 474 (2013).

*This work was supported by NSF/DMR-1704712 (FSU), NSF/DMR-1157490 (FSU) NSF/DMR-1644779 and the State of Florida (NHMFL), DOE, Office of BES, and Division of MSE (LANL), and NSF/DMR-1810310 (UC-San Diego).

–

Presenters

  • Keshav Shrestha

    • Idaho National Laboratory
    • Florida State University

Authors

  • Keshav Shrestha

    • Idaho National Laboratory
    • Florida State University

  • Laura H Greene

    • Florida State University
    • Physics, Florida State University
    • National High Magnetic Field Laboratory, Florida State University

  • Eric Bauer

    • Los Alamos National Laboratory, Los Alamos, NM 87545, USA
    • Los Alamos National Laboratory
    • MPA-CMMS, Los Alamos National Laboratory, Los Alamos, USA
    • MPA-CMMS, Los Alamos National Laboratory
    • Los Alamos National Laboratory, Los Alamos, New Mexico, USA
    • Los Alamos National Labs

  • Joe D Thompson

    • Los Alamos National Laboratory
    • MPA-CMMS, Los Alamos National Laboratory, Los Alamos, USA
    • MPA-CMMS, Los Alamos National Laboratory
    • Condensed Matter and Magnet Sciences, Los Alamos National Laboratory

  • You Lai

    • Florida State University
    • National High Magnetic Field Laboratory

  • Ryan Baumbach

    • National High Magnetic Field Laboratory, Florida State University
    • Florida State University
    • NHMFL-FSU
    • National High Magnetic Field Laboratory
    • National High Magnetic Field Laboratory and Florida State University
    • National High Magnetic Field Laboratory - Florida State University
    • NHMFL

  • Kalyan Sasmal

    • University of California, San Diego
    • Department of Physics, University of California, San Diego, La Jolla, CA 92093
    • Department of Physics, University of California, San Diego
    • Department of Physics, University of California, San Diego, CA 92093, USA

  • M Brian Maple

    • University of California, San Diego
    • Department of Physics, University of California, San Diego, La Jolla, CA 92093
    • Department of Physics, University of California, San Diego
    • UC San Diego
    • Physics, University of California, San Diego
    • Department of Physics, University of California, San Diego, CA 92093, USA
    • Physics, University of California, SanDiego

  • Wan Kyu Park

    • Florida State University
    • Physics, Florida State University
    • National High Magnetic Field Laboratory, Florida State University