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.

*Work at ORNL was supported by the U.S. Department of Energy, Basic Energy Sciences, Materials Sciences and Engineering Division.

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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