Insight into the metallurgy of UCoGe by electron-beam zone refining crystal growth

ORAL

Abstract

New insights into the phenomena of superconductivity have been enabled by the recently discovered U-based ferromagnetic superconducting compounds UGe2, UCoGe, URhGe, and UTe2. Sample quality in these compounds has proven to be a challenge for achieving a maximal superconducting transition temperature.  

We report the growth and characterization of single crystal UCoGe made by electron-beam floating-zone refining in an ultra-high vacuum environment. Once annealed at 900 C, the zone-refinied UCoGe samples show a well defined superconducting transition at ∽0.55 K and a ferromagnetic transition at ∽2.6 K through both electrical resistivity and heat capacity, consistent with samples grown by other methods. Using scanning electron microscopy we observed a new U-rich phase that collected in cracks and voids within the UCoGe crystal, which may be a key to improving future sample quality.

*Work was conducted at Los Alamos National Laboratory under the auspices of the U.S. Dept. of Energy (DOE), Office of Basic Energy Sciences, Division of Materials Sciences and Engineering. KEA acknowledge the U.S. DOE SCGSR program under contract number DE‐SC0014664 and U.S. DOE DE-FG02-05ER46248. A portion of this work was supported by the Los Alamos Laboratory Directed Research and Development program.

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Publication: Phys. Rev. Materials 5, 054803 (2021)

Presenters

  • Keenan Avers

    • Los Alamos National Laboratory
    • Northwestern University

Authors

  • Keenan Avers

    • Los Alamos National Laboratory
    • Northwestern University

  • Man D Nguyen

    • Northwestern University
    • Dept. Phys., Northwestern University

  • John W Scott

    • Northwestern University
    • Dept. Phys., Northwestern University

  • William P Halperin

    • Northwestern University
    • Dept. Phys., Northwestern University

  • Andrew Zimmerman

    • Harvard University
    • Harvard

  • 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

  • Joe D Thompson

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

  • Priscila Rosa

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