Magnetic and lattice coupling in the AFe$_2$As$_2$ (A=Ca, Ba, and Sr) compounds

ORAL

Abstract

Systematic elastic and inelastic neutron scattering studies of the AFe$_2$As$_2$ (A=Ca, Ba, and Sr) compounds reveal some common and distinguished properties that may shed light on the nature of the coupling between the magnetic and lattice degrees of freedom. We find, that for all three samples, the structural and antiferromagnetic (AFM) transition temperatures coincide within the experimental uncertainty of measurements. We also find that the AFM propagation vector is unequivocally along the long a- orthorhombic axis for all three compounds. The coupling between the magnetic and chemical structure is in play below the transition down to the lowest temperatures. More results and discussion on the nature of the transitions will be presented.

*Supported by the U.S. DOE under Contract No. DE-AC02-07CH11358.

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Authors

  • Haifeng Li

    • Ames Laboratory and Physics Department and Astronomy, Iowa State University, Ames, IA

  • David Vaknin

    • Ames Laboratory and Physics Department and Astronomy, Iowa State University, Ames, IA

  • J.L. Zarestky

    • Ames Laboratory and Physics Department and Astronomy, Iowa State University, Ames, IA
    • Ames Laboratory, US DOE and Iowa State University

  • Wei Tian

    • Ames Laboratory and Physics Department and Astronomy, Iowa State University, Ames, IA

  • Andreas Kreyssig

    • Ames Laboratory and Physics Department and Astronomy, Iowa State University, Ames, IA
    • Ames Laboratory and Iowa State University
    • Ames Laboratory, US DOE and Iowa State University
    • Ames Laboratory/Department of Physics and Astronomy
    • Ames Laboratory, US DOE, Iowa State University, Ames, IA 5001, USA

  • N. Ni

    • Ames Laboratory and Iowa State University
    • Ames Laboratory and Physics Department and Astronomy, Iowa State University, Ames, IA
    • Ames Lab / Iowa State University
    • Ames Laboratory, US DOE and Iowa State University
    • Iowa State University
    • Ames Laboratory/Department of Physics and Astronomy

  • S.L. Bud'ko

    • Ames Laboratory and Iowa State University
    • Ames Laboratory and Physics Department and Astronomy, Iowa State University, Ames, IA
    • Ames Laboratory
    • Ames Laboratory, US DOE and Iowa State University
    • Ames Laboratory/Iowa State University
    • Ames Laboratory/Department of Physics and Astronomy
    • Ames laboratory

  • P.C. Canfield

    • Ames Laboratory and Department of Physics and Astronomy, Iowa State Univeristy, Ames, Iowa 50011
    • Ames Laboratory and Iowa State University
    • Ames Laboratory and Physics Department and Astronomy, Iowa State University, Ames, IA
    • Ames Laboratory
    • Ames Laboratory, US DOE and Iowa State University
    • Ames Laboratory/Department of Physics and Astronomy
    • Ames Lab / Iowa State University
    • Ames Laboratory/Iowa State University

  • R.J. McQueeney

    • Ames Laboratory and Physics Department and Astronomy, Iowa State University, Ames, IA
    • Ames Laboratory and Iowa State University
    • Ames Laboratory, US DOE and Iowa State University
    • Ames Laboratory
    • Ames Laboratory/Department of Physics and Astronomy

  • Alan Goldman

    • Ames Laboratory and Physics Department and Astronomy, Iowa State University, Ames, IA
    • Ames Laboratory and Iowa State University
    • Ames Laboratory, US DOE and Iowa State University
    • Ames Laboratory
    • Ames Loboratory, US DOE and Iowa State University
    • Ames Laboratory/Department of Physics and Astronomy
    • Ames Laboratory, US DOE, Iowa State University, Ames, IA 5001, USA