AIP Advances (May 2017)

Thermal conductivity of ferrimagnet GdBaMn2O5.0 single crystals

  • J. C. Wu,
  • J. Y. Zhao,
  • H. S. Xu,
  • X. G. Liu,
  • A. A. Taskin,
  • Yoichi Ando,
  • X. Zhao,
  • X. F. Sun

DOI
https://doi.org/10.1063/1.4973294
Journal volume & issue
Vol. 7, no. 5
pp. 055807 – 055807-6

Abstract

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GdBaMn2O5.0 is a double-perovskite ferrimagnet consisting of pyramidal manganese layers. In this work, we study the in-plane and the c-axis thermal conductivities of GdBaMn2O5.0 single crystals at low temperatures down to 0.3 K and in high magnetic fields up to 14 T. The κc(T) curve shows a broad hump below the Néel temperature (TN = 144 K), which indicates the magnon heat transport along the c axis. Whereas, the κa(T) shows a kink at TN, caused by a magnon-phonon scattering effect. This anisotropic behavior is caused by the anisotropy of spin interactions along different directions. At very low temperatures, magnetic-field-induced changes of κa and κc, which is likely due to phonon scattering by free Gd3+ spins, is rather weak. This indicates that the spin coupling between Gd3+ and Mn2+/Mn3+ is rather strong at low temperatures.