Abstract
We report a temperature-dependent Raman scattering investigation of the multiferroic material bismuth ferrite (BFO). The observed loss of the Raman spectrum at the ferroelectric Curie temperature should be in agreement with a cubic structure of the high-temperature paraelectric phase. Surprisingly, the ferroelectric-to-paraelectric phase transition is not soft-mode driven, indicating a nonconventional ferroelectric. Furthermore, our results reveal pronounced phonon anomalies around the magnetic Néel temperature . We tentatively attribute these anomalies to the multiferroic character of BFO.
- Received 24 October 2005
DOI:https://doi.org/10.1103/PhysRevB.73.132101
©2006 American Physical Society