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Measured vs. Calculated Phonon Dispersions in the Cuprate HgBa<sub>2</sub>CuO<sub>4</sub>

ORAL

Abstract

Taking the prototypical high-Tc superconductor HgBa2CuO4 as an example, I will compare ab-initio density-functional-theory (DFT) calculations of the phonon dispersions to inelastic neutron scattering results that exhibit an anomaly in the Cu-O bond stretching branch. We have performed a series of calculations using several codes at different levels of approximation. Our results show good qualitative agreement for all codes, but only one gave a good quantitative agreement (better than 10%). All DFT calculations fail to reproduce the experimentally observed anomalous dispersion of the bond-stretching phonon branch. I will conclude my talk by mentioning other computational methods that may improve the agreement between the calculations and measurement.

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Presenters

  • Tyler Sterling

    University of Colorado, Boulder

Authors

  • Irada Ahmadova

    University of Colorado, Boulder

  • Tyler Sterling

    University of Colorado, Boulder

  • Aaron Sokolik

    University of Colorado, Boulder

  • Adrian Merritt

    Physics, University of Colorado, Boulder, University of Colorado, Boulder

  • Douglas L Abernathy

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

  • Mun K. Chan

    Los Alamos National Laboratory, Pulse Field Facility, National High Magnetic Field Laboratory, Los Alamos National Laboratory, National High Magnetic Field Laboratory, LANL, University of Minnesota, NHMFL

  • Yang Tang

    University of Minnesota, Physics and Astronomy, University of Minnesota

  • Guichuan Yu

    University of Minnesota

  • Martin Greven

    School of Physics and Astronomy, University of Minnesota, University of Minnesota, Physics and Astronomy, University of Minnesota, School of Physics and Astronomy, University of Minnesota Twin Cities

  • Dmitry Reznik

    University of Colorado, Boulder, University of Colorado at Boulder, Physics, University of Colorado, Boulder