Magnetocaloric effect measurements of the high field superconducting states in UTe<sub>2</sub>.

ORAL

Abstract

UTe2 has attracted significant attention in the last two years due to the discovery of potential chiral spin-triplet superconductivity evidenced by the unusually high critical fields and the small temperature variation of the NMR Knight shift. Even more intriguing a high field induced superconducting state was proposed to exist in UTe2 for field orientations between H||b and H||c emerging under ambient pressure between 40 to 60T. Here we present magnetocaloric measurements in pulsed magnetic fields up to 55T on new high quality UTe2 single crystals and show thermodynamic evidence of the high and low field superconducting phases in UTe2 as well as the field polarized state. The magnetocaloric measurements are supported by proximity detector oscillator (PDO) measurement which are sensitive to changes in the skin depth (electrical resistivity) and magnetic susceptibility – revealing a phase diagram in agreement with previous studies. The results are discussed with respect to vortex physics within the superconducting phases of UTe2.

*A portion of this work was performed at the National High Magnetic Field Laboratory, which is supported by the National Science Foundation Cooperative Agreement No. DMR-1644779 and the State of Florida. This work was supported by the G.T. Seaborg Institute Postdoctoral Fellow Program under project number 20210527CR. Sample synthesis was supported by the Los Alamos Laboratory Directed Research and Development program through project 20210064DR.

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Presenters

  • Rico Schoenemann

    • Los Alamos National Laboratory

Authors

  • Rico Schoenemann

    • Los Alamos National Laboratory

  • Priscila Rosa

    • Quantum Group, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
    • Los Alamos National Laboratory

  • Sean M Thomas

    • Los Alamos National Laboratory
    • Los Alamos National Laboratory, Los Alamos, New Mexico 87545, U.S.A.
    • Los Alamos National Laboratory, Los Alamos, New Mexico, 87545, USA

  • John Singleton

    • Los Alamos Natl Lab
    • NHMFL, Los Alamos National Lab
    • NHMFL/ LANL

  • Ross D McDonald

    • Los Alamos National Laboratory
    • National High Magnetic Field Laboratory, Los Alamos

  • Boris A Maiorov

    • Los Alamos National Laboratory

  • Vivien Zapf

    • Los Alamos Natl Lab
    • Los Alamos National Laboratory

  • Marcelo Jaime

    • Los Alamos Natl Lab