Phonon mode softening at the ferroelectric transition in Eu0.5Ba0.5TiO3

We have observed the effects of phonon mode softening at the ferroelectric transition in Eu0.5Ba0.5TiO3 by 151Eu Mössbauer spectroscopy. Both Eu2+ and Eu3+ spectral components are observed in the relative area ratio of 90% : 10% and both show a decrease in subspectral area at the transition, centred at 175 K, due to phonon mode softening. Surprisingly, the temperature dependence of the f-factor shows a much stronger response in the Eu3+ component than in the Eu2+ one. Preliminary analysis of neutron powder diffraction data rules out the possibility that some of the europium might be located on titanium sites. © 2010 Springer Science Business Media B.V.

Keywords

Ferroelectric materials, Phonons, Spectroscopy, Electrons, Electric dipole moments, Temperature dependence

Citation

Rowan-Weetaluktuk, W. N., Ryan, D. H., Sushkov, A. O., Eckel, S., Lamoreaux, S. K., Sushkov, O. P., Cadogan, J. M., Yethiraj, M. & Studer, A. J. (2010). Phonon mode softening at the ferroelectric transition in Eu 0.5 Ba 0.5 TiO 3. Hyperfine Interactions, 198, 1-4. doi:10.1007/s10751-010-0204-5