Strongly correlated itinerant magnetism near superconductivity in a magnetically doped transition metal dichalcogenide

ORAL

Abstract

Metallic ferromagnets with strongly interacting electrons often exhibit remarkable electronic phases such as ferromagnetic superconductivity, complex spin textures, and nontrivial topology. In this talk, I will discuss the synthesis of a layered magnetic metal NiTa4Se8 (or Ni1/4TaSe2) with a Curie temperature of 58 Kelvin. Magnetization data and density functional theory calculations indicate that the nickel atoms host uniaxial ferromagnetic order of about 0.7μB per atom, while an even smaller moment is generated in the itinerant tantalum conduction electrons. Strong correlations are evident in flat bands near the Fermi level, a high heat capacity coefficient, and a high Kadowaki-Woods ratio. Density functional theory calculations suggest that electron and hole Fermi surfaces in the ferromagnetic phase are associated with opposite spin polarization. When the system is diluted of magnetic ions, the samples become superconducting below about 2 Kelvin. I will briefly discuss possible mechanisms for superconductivity in this family.

*This work was supported by QSA, funded by the U.S. Department of Energy, Office of Science, National Quantum Information Science Research Centers

Publication: arXiv.2208.09475

Presenters

  • Nikola Maksimovic

    • Harvard University

Authors

  • Nikola Maksimovic

    • Harvard University
  • Ryan Day

    • UC Berkeley
    • University of California, Berkeley
  • Alexander Liebman-pelaez

    • UC Berkeley
  • Fanghui Wan

    • University of California, Berkeley
  • Nahyun Jo

    • University of Michigan
  • Aaron Bostwick

    • Lawrence Berkeley National Laboratory
    • LBNL
    • The Advanced Light Source
    • lawrence berkeley national lab
    • Lawrence Berkeley National Lab
    • Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, United States of America
    • Advanced Light Source, Lawrence Berkeley National Lab
  • Eli Rotenberg

    • Lawrence Berkeley National Laboratory
    • Advanced Light Source, Lawrence Berkeley National Lab
  • Sinead M Griffin

    • Lawrence Berkeley National Laboratory
    • Materials Science Division and Molecular Foundry, Berkeley Lab
    • Lawrence Berkeley National Lab
    • Materials Sciences Division and Molecular Foundry, LBNL
  • John Singleton

    • NHMFL/ LANL
  • James G Analytis

    • University of California, Berkeley
  • Christopher Jozwiak

    • Lawrence Berkeley National Laboratory
    • LBNL
    • The Advanced Light Source
    • lawrence berkeley national lab
    • Lawrence Berkeley National Lab
    • Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, United States of America
    • Advanced Light Source, Lawrence Berkeley National Lab