Symmetry analysis of magnetoelastic couplings in the Fe-based superconductors

ORAL

Abstract

Antiferromagnetism (AFM) is a reoccurring theme in the Fe-based superconductors. The stripe-type AFM on the Fe lattice in these compounds is accompanied by a sympathetic orthorhombic distortion of the tetragonal structure. This is not the only kind of magnetoelastic coupling possible between magnetic and structural degrees of freedom. Based on a symmetry analysis of the crystal structures we obtain the symmetry-allowed coupling terms in the Landau free energy. We propose that many of the compounds in this family (including FeSe, BaFe2As2 and CaKFe4As4) will develop a periodic structural modification when a magnetic field is applied to the AFM ordered phase. This should produce additional Bragg peaks which could provide a sensitive indicator of the AFM order under extreme conditions, such as in high pressure cells.

*We thank M. H. Christensen, R. M. Fernandes, S. L. Bud'ko, R. Flint, and P. P. Orth for their insightful discussions. This work is supported by the Gordon and Betty Moore Foundation's EPiQS Initiative through Grant GBMF4411 and the US DOE, Basic Energy Sciences under Contract No. DE-AC02-07CH11358.

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Presenters

  • William Meier

    • Ames Laboratory and Dept. of Physics, Iowa State University
    • Ames Laboratory, Iowa State University
    • Ames Laboratory and Dept. of Phys. and Astro.,, Iowa State Univ.
    • Iowa State University and Ames Laboratory
    • Ames Laboratory & Department of Physics, Iowa State University

Authors

  • William Meier

    • Ames Laboratory and Dept. of Physics, Iowa State University
    • Ames Laboratory, Iowa State University
    • Ames Laboratory and Dept. of Phys. and Astro.,, Iowa State Univ.
    • Iowa State University and Ames Laboratory
    • Ames Laboratory & Department of Physics, Iowa State University

  • Andreas Kreyssig

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

  • Paul Canfield

    • Ames Laboratory and Dept. of Physics, Iowa State University
    • Ames Laboratory, U.S. DOE, Iowa State University, Ames, Iowa 50011, USA.
    • Ames Laboratory
    • Iowa State University
    • Department of Physics, Iowa State University, Ames Laboratory, Ames, Iowa 50011, USA
    • Ames Laboratory, Iowa State University
    • Ames Laboratory/Iowa State University
    • Iowa State University and Ames Laboratory
    • Ames Laboratory and Iowa State University, Ames, IA, USA
    • Ames Laboratory and Dept. of Phys. and Astro.,, Iowa State Univ.
    • Ames Laboratory and Department of Physics & Astronomy, Iowa State University, Ames, IA 50010, USA
    • Ames Lab & Dept of Physics and Astronomy, Iowa State University
    • Department of Physics & Astronomy, Iowa State University
    • Department of physics and astronomy, Iowa State University/Ames Laboratory
    • Physics, Iowa State University/Ames Laboratory
    • Ames Laboratory & Iowa State University
    • Physics, Iowa State University