Coupling between magnon and ligand-field excitations in magnetoelectric Tb3Fe5O12 garnet

Kang T. D. , Standard E., Ahn K. H. , Sirenko A. A. , CARR G. L. , PARK S., ...More

PHYSICAL REVIEW B, vol.82, no.1, 2010 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 82 Issue: 1
  • Publication Date: 2010
  • Doi Number: 10.1103/physrevb.82.014414
  • Title of Journal : PHYSICAL REVIEW B


The spectra of far-infrared transmission in Tb3Fe5O12 magnetoelectric single crystals have been studied in the range between 15 and 100 cm(-1), in magnetic fields up to 10 T, and for temperatures between 5 and 150 K. We attribute some of the observed infrared-active excitations to electric dipole transitions between ligand-field split states of Tb3+ ions. Anticrossing between the magnetic exchange excitation and the ligand-field transition occurs at the temperature between 60 and 80 K. The corresponding coupling energy for this interaction is 6 cm(-1). Temperature-induced softening of the hybrid IR excitation correlates with the increase in the static dielectric constant. We discuss the possibility for hybrid excitations of magnons and ligand-field states and their possible connection to the magnetoelectric effect in Tb3Fe5O12.