Influence of magnetism on phonons in CaFe$_{2}$As$_{2}$ as seen via inelastic x-ray scattering

ORAL

Abstract

In the iron pnictides, the strong sensitivity of the iron magnetic moment to the arsenic position suggests a significant relationship between phonons and magnetism. We measured the phonon dispersion of several branches in the high-temperature tetragonal phase of CaFe$_{2}$As$_{2}$ using inelastic x-ray scattering on single-crystal samples. These measurements were compared to\textit{ ab initio }calculations of the phonons. Spin-polarized calculations imposing the antiferromagnetic order present in the low-temperature tetragonal phase dramatically improve agreement between theory and experiment. This is discussed in terms of the strong antiferromagnetic correlations that are known to persist in the tetragonal phase.

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Authors

  • Steven Hahn

    Ames Laboratory and Iowa State University

  • Michael Turner

    Illinois Institute of Technology, Bettendorf High School, Bettendorf, IA, Mississippi Bend Area Education Agency, Bettendorf, IA, Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA, Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, IA 50011, USA, Max-Planck-Institut fuer Mikrostrukturphysik, Halle, Germany, CNRS, Universite Lyon I, France, Freie Universitaet Berlin, Germany, University of Jyvaskila, Finaland, Iowa State University/Ames Laboratory, Materials Science Division, Argonne National Laboratory and Department of Chemistry, Northwestern University, Materials Science Division, Argonne National Laboratory, Advanced Photon Source, Argonne National Laboratory, Ames Laboratory and Iowa State University, Indiana University, Illinois State University, University of Iowa, Louisiana State University, University of Warwick, Rutherford Appleton Laboratory, Coe College, University of Northern Iowa, Iowa State University and Ames Laboratory, University of Illinois, Ames Laboratory, University of Florida, Tulane University, The Department of Physics and The James Franck Institute, The University of Chicago, J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS 66506, Department of Physics, Augustana College, Sioux Falls, SD 57197, Intense Laser Physics Theory Unit, Illinois State University, Argonne National Laboratory, Dr, Drake University, Physics Department, Ocean University of China, Qingdao, Physics Department, Southern Illinois University Carbondale, Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, Department of Physics and Astronomy, University of Missouri, Columbia, Missouri 65211, USA, Department of Physics, The University of Texas at Austin, Austin, Texas 78712, USA, NEST-CNR-INFM and Scuola Normale Superiore, I-56126 Pisa, Italy, University of New Hampshire Department of Physics, University of Chicago

  • Michael Turner

    Illinois Institute of Technology, Bettendorf High School, Bettendorf, IA, Mississippi Bend Area Education Agency, Bettendorf, IA, Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA, Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, IA 50011, USA, Max-Planck-Institut fuer Mikrostrukturphysik, Halle, Germany, CNRS, Universite Lyon I, France, Freie Universitaet Berlin, Germany, University of Jyvaskila, Finaland, Iowa State University/Ames Laboratory, Materials Science Division, Argonne National Laboratory and Department of Chemistry, Northwestern University, Materials Science Division, Argonne National Laboratory, Advanced Photon Source, Argonne National Laboratory, Ames Laboratory and Iowa State University, Indiana University, Illinois State University, University of Iowa, Louisiana State University, University of Warwick, Rutherford Appleton Laboratory, Coe College, University of Northern Iowa, Iowa State University and Ames Laboratory, University of Illinois, Ames Laboratory, University of Florida, Tulane University, The Department of Physics and The James Franck Institute, The University of Chicago, J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS 66506, Department of Physics, Augustana College, Sioux Falls, SD 57197, Intense Laser Physics Theory Unit, Illinois State University, Argonne National Laboratory, Dr, Drake University, Physics Department, Ocean University of China, Qingdao, Physics Department, Southern Illinois University Carbondale, Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, Department of Physics and Astronomy, University of Missouri, Columbia, Missouri 65211, USA, Department of Physics, The University of Texas at Austin, Austin, Texas 78712, USA, NEST-CNR-INFM and Scuola Normale Superiore, I-56126 Pisa, Italy, University of New Hampshire Department of Physics, University of Chicago

  • Michael Turner

    Illinois Institute of Technology, Bettendorf High School, Bettendorf, IA, Mississippi Bend Area Education Agency, Bettendorf, IA, Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA, Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, IA 50011, USA, Max-Planck-Institut fuer Mikrostrukturphysik, Halle, Germany, CNRS, Universite Lyon I, France, Freie Universitaet Berlin, Germany, University of Jyvaskila, Finaland, Iowa State University/Ames Laboratory, Materials Science Division, Argonne National Laboratory and Department of Chemistry, Northwestern University, Materials Science Division, Argonne National Laboratory, Advanced Photon Source, Argonne National Laboratory, Ames Laboratory and Iowa State University, Indiana University, Illinois State University, University of Iowa, Louisiana State University, University of Warwick, Rutherford Appleton Laboratory, Coe College, University of Northern Iowa, Iowa State University and Ames Laboratory, University of Illinois, Ames Laboratory, University of Florida, Tulane University, The Department of Physics and The James Franck Institute, The University of Chicago, J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS 66506, Department of Physics, Augustana College, Sioux Falls, SD 57197, Intense Laser Physics Theory Unit, Illinois State University, Argonne National Laboratory, Dr, Drake University, Physics Department, Ocean University of China, Qingdao, Physics Department, Southern Illinois University Carbondale, Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, Department of Physics and Astronomy, University of Missouri, Columbia, Missouri 65211, USA, Department of Physics, The University of Texas at Austin, Austin, Texas 78712, USA, NEST-CNR-INFM and Scuola Normale Superiore, I-56126 Pisa, Italy, University of New Hampshire Department of Physics, University of Chicago

  • Michael Turner

    Illinois Institute of Technology, Bettendorf High School, Bettendorf, IA, Mississippi Bend Area Education Agency, Bettendorf, IA, Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA, Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, IA 50011, USA, Max-Planck-Institut fuer Mikrostrukturphysik, Halle, Germany, CNRS, Universite Lyon I, France, Freie Universitaet Berlin, Germany, University of Jyvaskila, Finaland, Iowa State University/Ames Laboratory, Materials Science Division, Argonne National Laboratory and Department of Chemistry, Northwestern University, Materials Science Division, Argonne National Laboratory, Advanced Photon Source, Argonne National Laboratory, Ames Laboratory and Iowa State University, Indiana University, Illinois State University, University of Iowa, Louisiana State University, University of Warwick, Rutherford Appleton Laboratory, Coe College, University of Northern Iowa, Iowa State University and Ames Laboratory, University of Illinois, Ames Laboratory, University of Florida, Tulane University, The Department of Physics and The James Franck Institute, The University of Chicago, J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS 66506, Department of Physics, Augustana College, Sioux Falls, SD 57197, Intense Laser Physics Theory Unit, Illinois State University, Argonne National Laboratory, Dr, Drake University, Physics Department, Ocean University of China, Qingdao, Physics Department, Southern Illinois University Carbondale, Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, Department of Physics and Astronomy, University of Missouri, Columbia, Missouri 65211, USA, Department of Physics, The University of Texas at Austin, Austin, Texas 78712, USA, NEST-CNR-INFM and Scuola Normale Superiore, I-56126 Pisa, Italy, University of New Hampshire Department of Physics, University of Chicago

  • Michael Turner

    Illinois Institute of Technology, Bettendorf High School, Bettendorf, IA, Mississippi Bend Area Education Agency, Bettendorf, IA, Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA, Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, IA 50011, USA, Max-Planck-Institut fuer Mikrostrukturphysik, Halle, Germany, CNRS, Universite Lyon I, France, Freie Universitaet Berlin, Germany, University of Jyvaskila, Finaland, Iowa State University/Ames Laboratory, Materials Science Division, Argonne National Laboratory and Department of Chemistry, Northwestern University, Materials Science Division, Argonne National Laboratory, Advanced Photon Source, Argonne National Laboratory, Ames Laboratory and Iowa State University, Indiana University, Illinois State University, University of Iowa, Louisiana State University, University of Warwick, Rutherford Appleton Laboratory, Coe College, University of Northern Iowa, Iowa State University and Ames Laboratory, University of Illinois, Ames Laboratory, University of Florida, Tulane University, The Department of Physics and The James Franck Institute, The University of Chicago, J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS 66506, Department of Physics, Augustana College, Sioux Falls, SD 57197, Intense Laser Physics Theory Unit, Illinois State University, Argonne National Laboratory, Dr, Drake University, Physics Department, Ocean University of China, Qingdao, Physics Department, Southern Illinois University Carbondale, Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, Department of Physics and Astronomy, University of Missouri, Columbia, Missouri 65211, USA, Department of Physics, The University of Texas at Austin, Austin, Texas 78712, USA, NEST-CNR-INFM and Scuola Normale Superiore, I-56126 Pisa, Italy, University of New Hampshire Department of Physics, University of Chicago

  • Michael Turner

    Illinois Institute of Technology, Bettendorf High School, Bettendorf, IA, Mississippi Bend Area Education Agency, Bettendorf, IA, Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA, Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, IA 50011, USA, Max-Planck-Institut fuer Mikrostrukturphysik, Halle, Germany, CNRS, Universite Lyon I, France, Freie Universitaet Berlin, Germany, University of Jyvaskila, Finaland, Iowa State University/Ames Laboratory, Materials Science Division, Argonne National Laboratory and Department of Chemistry, Northwestern University, Materials Science Division, Argonne National Laboratory, Advanced Photon Source, Argonne National Laboratory, Ames Laboratory and Iowa State University, Indiana University, Illinois State University, University of Iowa, Louisiana State University, University of Warwick, Rutherford Appleton Laboratory, Coe College, University of Northern Iowa, Iowa State University and Ames Laboratory, University of Illinois, Ames Laboratory, University of Florida, Tulane University, The Department of Physics and The James Franck Institute, The University of Chicago, J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS 66506, Department of Physics, Augustana College, Sioux Falls, SD 57197, Intense Laser Physics Theory Unit, Illinois State University, Argonne National Laboratory, Dr, Drake University, Physics Department, Ocean University of China, Qingdao, Physics Department, Southern Illinois University Carbondale, Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, Department of Physics and Astronomy, University of Missouri, Columbia, Missouri 65211, USA, Department of Physics, The University of Texas at Austin, Austin, Texas 78712, USA, NEST-CNR-INFM and Scuola Normale Superiore, I-56126 Pisa, Italy, University of New Hampshire Department of Physics, University of Chicago

  • Michael Turner

    Illinois Institute of Technology, Bettendorf High School, Bettendorf, IA, Mississippi Bend Area Education Agency, Bettendorf, IA, Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA, Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, IA 50011, USA, Max-Planck-Institut fuer Mikrostrukturphysik, Halle, Germany, CNRS, Universite Lyon I, France, Freie Universitaet Berlin, Germany, University of Jyvaskila, Finaland, Iowa State University/Ames Laboratory, Materials Science Division, Argonne National Laboratory and Department of Chemistry, Northwestern University, Materials Science Division, Argonne National Laboratory, Advanced Photon Source, Argonne National Laboratory, Ames Laboratory and Iowa State University, Indiana University, Illinois State University, University of Iowa, Louisiana State University, University of Warwick, Rutherford Appleton Laboratory, Coe College, University of Northern Iowa, Iowa State University and Ames Laboratory, University of Illinois, Ames Laboratory, University of Florida, Tulane University, The Department of Physics and The James Franck Institute, The University of Chicago, J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS 66506, Department of Physics, Augustana College, Sioux Falls, SD 57197, Intense Laser Physics Theory Unit, Illinois State University, Argonne National Laboratory, Dr, Drake University, Physics Department, Ocean University of China, Qingdao, Physics Department, Southern Illinois University Carbondale, Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, Department of Physics and Astronomy, University of Missouri, Columbia, Missouri 65211, USA, Department of Physics, The University of Texas at Austin, Austin, Texas 78712, USA, NEST-CNR-INFM and Scuola Normale Superiore, I-56126 Pisa, Italy, University of New Hampshire Department of Physics, University of Chicago

  • Michael Turner

    Illinois Institute of Technology, Bettendorf High School, Bettendorf, IA, Mississippi Bend Area Education Agency, Bettendorf, IA, Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA, Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, IA 50011, USA, Max-Planck-Institut fuer Mikrostrukturphysik, Halle, Germany, CNRS, Universite Lyon I, France, Freie Universitaet Berlin, Germany, University of Jyvaskila, Finaland, Iowa State University/Ames Laboratory, Materials Science Division, Argonne National Laboratory and Department of Chemistry, Northwestern University, Materials Science Division, Argonne National Laboratory, Advanced Photon Source, Argonne National Laboratory, Ames Laboratory and Iowa State University, Indiana University, Illinois State University, University of Iowa, Louisiana State University, University of Warwick, Rutherford Appleton Laboratory, Coe College, University of Northern Iowa, Iowa State University and Ames Laboratory, University of Illinois, Ames Laboratory, University of Florida, Tulane University, The Department of Physics and The James Franck Institute, The University of Chicago, J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS 66506, Department of Physics, Augustana College, Sioux Falls, SD 57197, Intense Laser Physics Theory Unit, Illinois State University, Argonne National Laboratory, Dr, Drake University, Physics Department, Ocean University of China, Qingdao, Physics Department, Southern Illinois University Carbondale, Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, Department of Physics and Astronomy, University of Missouri, Columbia, Missouri 65211, USA, Department of Physics, The University of Texas at Austin, Austin, Texas 78712, USA, NEST-CNR-INFM and Scuola Normale Superiore, I-56126 Pisa, Italy, University of New Hampshire Department of Physics, University of Chicago

  • Michael Turner

    Illinois Institute of Technology, Bettendorf High School, Bettendorf, IA, Mississippi Bend Area Education Agency, Bettendorf, IA, Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA, Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, IA 50011, USA, Max-Planck-Institut fuer Mikrostrukturphysik, Halle, Germany, CNRS, Universite Lyon I, France, Freie Universitaet Berlin, Germany, University of Jyvaskila, Finaland, Iowa State University/Ames Laboratory, Materials Science Division, Argonne National Laboratory and Department of Chemistry, Northwestern University, Materials Science Division, Argonne National Laboratory, Advanced Photon Source, Argonne National Laboratory, Ames Laboratory and Iowa State University, Indiana University, Illinois State University, University of Iowa, Louisiana State University, University of Warwick, Rutherford Appleton Laboratory, Coe College, University of Northern Iowa, Iowa State University and Ames Laboratory, University of Illinois, Ames Laboratory, University of Florida, Tulane University, The Department of Physics and The James Franck Institute, The University of Chicago, J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS 66506, Department of Physics, Augustana College, Sioux Falls, SD 57197, Intense Laser Physics Theory Unit, Illinois State University, Argonne National Laboratory, Dr, Drake University, Physics Department, Ocean University of China, Qingdao, Physics Department, Southern Illinois University Carbondale, Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, Department of Physics and Astronomy, University of Missouri, Columbia, Missouri 65211, USA, Department of Physics, The University of Texas at Austin, Austin, Texas 78712, USA, NEST-CNR-INFM and Scuola Normale Superiore, I-56126 Pisa, Italy, University of New Hampshire Department of Physics, University of Chicago

  • Michael Turner

    Illinois Institute of Technology, Bettendorf High School, Bettendorf, IA, Mississippi Bend Area Education Agency, Bettendorf, IA, Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA, Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, IA 50011, USA, Max-Planck-Institut fuer Mikrostrukturphysik, Halle, Germany, CNRS, Universite Lyon I, France, Freie Universitaet Berlin, Germany, University of Jyvaskila, Finaland, Iowa State University/Ames Laboratory, Materials Science Division, Argonne National Laboratory and Department of Chemistry, Northwestern University, Materials Science Division, Argonne National Laboratory, Advanced Photon Source, Argonne National Laboratory, Ames Laboratory and Iowa State University, Indiana University, Illinois State University, University of Iowa, Louisiana State University, University of Warwick, Rutherford Appleton Laboratory, Coe College, University of Northern Iowa, Iowa State University and Ames Laboratory, University of Illinois, Ames Laboratory, University of Florida, Tulane University, The Department of Physics and The James Franck Institute, The University of Chicago, J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS 66506, Department of Physics, Augustana College, Sioux Falls, SD 57197, Intense Laser Physics Theory Unit, Illinois State University, Argonne National Laboratory, Dr, Drake University, Physics Department, Ocean University of China, Qingdao, Physics Department, Southern Illinois University Carbondale, Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, Department of Physics and Astronomy, University of Missouri, Columbia, Missouri 65211, USA, Department of Physics, The University of Texas at Austin, Austin, Texas 78712, USA, NEST-CNR-INFM and Scuola Normale Superiore, I-56126 Pisa, Italy, University of New Hampshire Department of Physics, University of Chicago

  • Michael Turner

    Illinois Institute of Technology, Bettendorf High School, Bettendorf, IA, Mississippi Bend Area Education Agency, Bettendorf, IA, Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA, Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, IA 50011, USA, Max-Planck-Institut fuer Mikrostrukturphysik, Halle, Germany, CNRS, Universite Lyon I, France, Freie Universitaet Berlin, Germany, University of Jyvaskila, Finaland, Iowa State University/Ames Laboratory, Materials Science Division, Argonne National Laboratory and Department of Chemistry, Northwestern University, Materials Science Division, Argonne National Laboratory, Advanced Photon Source, Argonne National Laboratory, Ames Laboratory and Iowa State University, Indiana University, Illinois State University, University of Iowa, Louisiana State University, University of Warwick, Rutherford Appleton Laboratory, Coe College, University of Northern Iowa, Iowa State University and Ames Laboratory, University of Illinois, Ames Laboratory, University of Florida, Tulane University, The Department of Physics and The James Franck Institute, The University of Chicago, J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS 66506, Department of Physics, Augustana College, Sioux Falls, SD 57197, Intense Laser Physics Theory Unit, Illinois State University, Argonne National Laboratory, Dr, Drake University, Physics Department, Ocean University of China, Qingdao, Physics Department, Southern Illinois University Carbondale, Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, Department of Physics and Astronomy, University of Missouri, Columbia, Missouri 65211, USA, Department of Physics, The University of Texas at Austin, Austin, Texas 78712, USA, NEST-CNR-INFM and Scuola Normale Superiore, I-56126 Pisa, Italy, University of New Hampshire Department of Physics, University of Chicago

  • Michael Turner

    Illinois Institute of Technology, Bettendorf High School, Bettendorf, IA, Mississippi Bend Area Education Agency, Bettendorf, IA, Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA, Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, IA 50011, USA, Max-Planck-Institut fuer Mikrostrukturphysik, Halle, Germany, CNRS, Universite Lyon I, France, Freie Universitaet Berlin, Germany, University of Jyvaskila, Finaland, Iowa State University/Ames Laboratory, Materials Science Division, Argonne National Laboratory and Department of Chemistry, Northwestern University, Materials Science Division, Argonne National Laboratory, Advanced Photon Source, Argonne National Laboratory, Ames Laboratory and Iowa State University, Indiana University, Illinois State University, University of Iowa, Louisiana State University, University of Warwick, Rutherford Appleton Laboratory, Coe College, University of Northern Iowa, Iowa State University and Ames Laboratory, University of Illinois, Ames Laboratory, University of Florida, Tulane University, The Department of Physics and The James Franck Institute, The University of Chicago, J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS 66506, Department of Physics, Augustana College, Sioux Falls, SD 57197, Intense Laser Physics Theory Unit, Illinois State University, Argonne National Laboratory, Dr, Drake University, Physics Department, Ocean University of China, Qingdao, Physics Department, Southern Illinois University Carbondale, Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, Department of Physics and Astronomy, University of Missouri, Columbia, Missouri 65211, USA, Department of Physics, The University of Texas at Austin, Austin, Texas 78712, USA, NEST-CNR-INFM and Scuola Normale Superiore, I-56126 Pisa, Italy, University of New Hampshire Department of Physics, University of Chicago