Single Crystal Diffuse Scattering Investigation of Nematic Fluctuations in (Ba,Na)Fe2As2

ORAL

Abstract

The phase competition between nematic order and superconductivity has been intensively investigated in iron-based superconductors. Recent neutron pair-distribution-function (PDF) measurements on polycrystaline samples provide evidence of dynamic orthorhombic distortions, even within the C4 tetragonal magnetic phase of hole-doped compounds [1]. We present synchrotron x-ray measurements of diffuse scattering from single crystals of (Ba,Na)Fe2As2, which show that these nematic fluctuations are predominantly two-dimensional. The measurements cover a sufficiently large volume of reciprocal space that they can be transformed into real space, generating 3D PDFs, from which both in-plane and out-of-plane correlation lengths are determined as a function of temperature and dopant concentration. These results will be compared to other measurements of the nematic susceptibility.

[1] B. A. Frandsen, et al., Phys Rev Lett 119, 187001 (2017).

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Presenters

  • Raymond Osborn

    Materials Science Division, Argonne National Laboratory, Argonne National Laboratory

Authors

  • Raymond Osborn

    Materials Science Division, Argonne National Laboratory, Argonne National Laboratory

  • Matthew Krogstad

    Materials Science Division, Argonne National Laboratory, Argonne National Laboratory

  • Stephan Rosenkranz

    Materials Science Division, Argonne National Laboratory, Argonne National Laboratory

  • Omar Chmaissem

    Northern Illinois University, Department of Physics, Northern Illinois University, Argonne National Laboratory

  • Puspa R Upreti

    Department of Physics, Northern Illinois University

  • Ryan Stadel

    Northern Illinois University, Department of Physics, Northern Illinois University

  • Keith Taddei

    Oak Ridge National Laboratory, Neutron Scattering Division, Oak Ridge National Laboratory, HFIR, Oak Ridge National Laboratory