Purely Magnetic Nature of Spin-Reorientation Transitions in Orthoferrites.

POSTER

Abstract

Magnetic and structural characteristics of ErFeO$_3$, TmFeO$_3$ and YbFeO$_3$ single crystals were studied in the vicinity of the spin-reorientation transitions. In all crystals the behavior of the absolute value of the magnetization $M(T)$ and the rotation angle $\theta(T)$ are incompatible with the conventional Landau mean field theory but can be described with no fitting parameters by the proposed modified mean field theory. X-ray measurements found no symmetry-lowering lattice distortions and suggest a purely magnetic nature of the transition. Successful fitting of experimental data in several materials with a wide range of magnetic parameters demonstrates the generality of the proposed description of $\Gamma_4(G_x, F_z) \to \Gamma_{24}(G_{xz}, F_{xz}) \to \Gamma_2(G_z, F_x)$ orientation phase transitions in orthoferrites.

Authors

  • Ya. B. Bazaliy

    • Instituut Lorentz, Leiden University, The Netherlands and Dept. of Physics and Astronomy, University of South Carolina
    • Instituut Lorentz, Leiden University and Dept. of Physics and Astronomy, University of South Carolina

  • L. T. Tsymbal

  • L. T. Tsymbal

  • V. I. Kamenev

    • O. Galkin Donetsk Physics and Technology Institute, National Academy of Science, Ukraine

  • G. N. Kakazei

    • Institute of Magnetism, National Academy of Science, Ukraine

  • F. J. Palomares

    • Instituto de Ciencia de Materiales de Madrid, Spain

  • P. E. Wigen

    • Department of Physics, Ohio State University