Resonant Ultrasound studies of double perovskites A$_{2}$FeReO$_{6}$ (A=Ba, Ca)

ORAL

Abstract

The elastic response as a function of temperature (50-380) K and magnetic field (0-2) T has been studied using Resonant Ultrasound Spectroscopy (RUS) for the polycrystalline double perovskites A$_{2}$FeReO$_{6}$ (A= Ba, Ca). An elastic softening over a wide temperature range is observed below the Curie temperature (T$_{c}$ $\sim$ 305K) of Ba$_{2}$FeReO$_{6}$, which is suppressed upon the application of a magnetic field. For Ca$_{2}$FeReO$_{6}$, both the longitudinal and shear modulus show a step-like softening starting around 140K, indicative of a structural transition. A large change in the magnetoelastic coupling constant is observed at this temperature, suggesting that this transition is strongly coupled to the magnetic properties of this material.

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Authors

  • Ling Li

    Dept. Materials Science and Engineering, The University of Tennessee

  • Jiaqiang Yan

    Dept. Materials Science and Engineering, The University of Tennessee and Materials Science and Technology Division, Oak Ridge National Laboratory

  • David Mandrus

    University of Tennessee, Dept. Materials Science and Engineering, The University of Tennessee and Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge National Laboratory, The University of Tennessee/Oak Ridge National Laboratory, Materials Science and Engineering, University of Tennessee

  • Veerle Keppens

    Dept. Materials Science and Engineering, The University of Tennessee