Competition between spin-vortex crystal and superconductivity in Ni-doped CaKFe<sub>4</sub>As<sub>4</sub>

ORAL

Abstract

CaKFe4As4 is a member of the iron arsenide superconductors in which partial substitution of Ni for Fe shifts the ground state from superconducting to antiferromagnetically (AFM) ordered. Employing neutron diffraction we determined that the AFM order is a non-collinear, commensurate structure with a hedgehog spin-vortex crystal (SVC) arrangement in the Fe planes and a simple AFM stacking perpendicular to them. The long-range SVC order coexists with superconductivity, however, similar to the doped 122 compounds with collinear stripe AFM, the ordered magnetic moment is gradually suppressed as the superconducting order parameter develops. Almost complete suppression of the AFM order is observed in a sample close to the critical Ni concentration, resulting in a back-bending of the AFM-transition-temperature phase line as a function of concentration. This supports the notion that both collinear and non-collinear magnetism as well as superconductivity compete for the same Fermi-surface nested electrons in the iron arsenide superconductors.

*This work was supported by the U. S. DOE, BES, DMSE, under Contract DE-AC02-07CH11358. This research used resources at HFIR, a U. S. DOE Office of Science User Facility operated by the Oak Ridge National Laboratory.

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Presenters

  • Andreas Kreyssig

    • Ames Laboratory, Ames, IA 50011, USA; Iowa State University, Ames IA 50011, USA
    • Physics and Astronomy, Iowa State University/Ames Laboratory
    • Department of Physics and Astronomy, Iowa State University/Ames Laboratory
    • Ames Laboratory, Iowa State University, Dept. of Physics and Astronomy, Ames
    • Ames Laboratory, Ames, IA 50011, USA; Iowa State University, Ames, IA 50011, USA

Authors

  • Andreas Kreyssig

    • Ames Laboratory, Ames, IA 50011, USA; Iowa State University, Ames IA 50011, USA
    • Physics and Astronomy, Iowa State University/Ames Laboratory
    • Department of Physics and Astronomy, Iowa State University/Ames Laboratory
    • Ames Laboratory, Iowa State University, Dept. of Physics and Astronomy, Ames
    • Ames Laboratory, Ames, IA 50011, USA; Iowa State University, Ames, IA 50011, USA

  • John Wilde

    • Physics and Astronomy, Iowa State University/Ames Laboratory
    • Department of Physics and Astronomy, Iowa State University/Ames Laboratory
    • Ames Laboratory, Iowa State University, Dept. of Physics and Astronomy, Ames

  • Anna E. Böhmer

    • Ames Laboratory, Iowa State University, Ames; Karlsruhe Institute of Technology, Karlsruhe

  • Wei Tian

    • Oak Ridge National Lab
    • Neutron Scattering Science Division, Oak Ridge National Laboratory
    • Oak Ridge National Laboratory
    • Oak Ridge National Laboratory, Oak Ridge

  • William Meier

    • Oak Ridge National Lab
    • Ames Laboratory, Iowa State University, Ames; Oak Ridge National Laboratory, Oak Ridge
    • Ames Laboratory, Iowa State University

  • Bing Li

    • Ames Laboratory, Ames, IA 50011, USA; Iowa State University, Ames IA 50011, USA
    • Ames Laboratory, Iowa State University, Dept. of Physics and Astronomy, Ames
    • Ames Laboratory, Ames, IA 50011, USA; Iowa State University, Ames, IA 50011, USA

  • Benjamin G. Ueland

    • Ames Laboratory, Iowa State University, Dept. of Physics and Astronomy, Ames

  • Mingyu Xu

    • Iowa State University
    • Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA
    • Ames Laboratory, Iowa State University, Dept. of Physics and Astronomy, Ames
    • Ames Laboratory, Iowa State University

  • Sergey L. Bud'ko

    • Ames Laboratory, Iowa State University, Dept. of Physics and Astronomy, Ames
    • Ames Laboratory, Iowa State University
    • Department of Physics and Astronomy, Ames Laboratory/Iowa State Univeristy

  • Paul C. Canfield

    • Ames Laboratory, Iowa State University, Dept. of Physics and Astronomy, Ames

  • Robert McQueeney

    • Ames Laboratory, Ames, IA 50011, USA; Iowa State University, Ames IA 50011, USA
    • Iowa State University
    • Ames Laboratory, Iowa State University
    • Physics and Astronomy, Iowa State University/Ames Laboratory
    • Ames Laboratory, Iowa State University, Dept. of Physics and Astronomy, Ames
    • Ames Laboratory, Ames, IA 50011, USA; Iowa State University, Ames, IA 50011, USA

  • Alan I. Goldman

    • Ames Laboratory, Iowa State University, Dept. of Physics and Astronomy, Ames