Relaxational and Vibrational Dynamics of 0.44Pb(Mg_1/3Nb_2/3)O₃-0.56PbTiO₃ Single Crystal Probed by Micro-Raman Scattering

Abstract

Raman scattering of a 0.44Pb(Mg_1/3Nb_2/3)O₃-0.56PbTiO₃ (PMN-56PT) single crystal was measured to examine the growing process of polar nanoregions (PNRs) of a PT rich relaxor in a paraelectric cubic phase. As a common nature of relaxors, the central peak (CP) intensity shows anomalies at three characteristic temperatures: Burns temperature T_B ∼ 673 K, intermediate temperature T* ∼ 603 K, and cubic-tetragonal phase transition temperature T_C-T ∼ 533 K. The highest temperature anomaly at T_B is attributed to the local symmetry breaking due to the appearance of PNRs. While, T* is originated from the rapid growth of PNRs and their dynamic-static transition.

Keywords:

• Ferroelectric
• perovskite
• relaxor
• optical mode
• Raman scattering
• polar nanoregions
• phase transition

Acknowledgment

The authors are thankful to Mr. Rahaman and Mr. Yamada for their support in Raman scattering measurements.

Funding

This work has been supported in part by the JSPS KAKENHI Grant.