Phase transitions in PbZr_0.72Sn_0.28O₃ single crystals studied by Raman spectroscopy

ABSTRACT

Raman light scattering measurements in the temperature range from 80 to 830 K were performed on a PbZr_0.72Sn_0.28O₃ single crystal. The frequencies of the Raman lines were analyzed and discussed in terms of the sequence of structural phase transitions. It was found that Raman spectrum displays important changes near 440, 480 and 493 K. The incorporation of more than 25 mol% of Sn⁴⁺ ions into the structure of PbZrO₃ enhances polar fluctuations above T_C as compared to the less Sn-doped crystals. These fluctuations lead to appearance of a ferroelastic intermediate phase below T_C. It is demonstrated that the structural phase transformation in PbZr_0.72Sn_0.28O₃ can be considered as the result of softening of a number of modes.

KEYWORDS:

• Antiferroelectrics
• phase transitions
• Raman spectroscopy
• modes softening
• precursor effects

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This research was co-financed by the European Regional Development Fund under the infrastructure and Environment Programme [grant number UDA-POIS.13.01-023/09-00]. This research was also supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology [2013R1A1A2006582].