Growth and characterization of ferroelectric Pb(Sc_1/2Nb_1/2)O₃ single crystals

Abstract

Single crystals of Pb(Sc_1/2Nb_1/2)O₃ were grown by the high-temperature solution method using PbO + B₂O₃ as flux. The size of the as-grown crystals varies from 1 to 2 mm. X-ray diffraction indicates a pure perovskite phase without B-site ordering. Polarized light microscopy shows that the crystals are of rhombohedral symmetry at room temperature and become cubic at T_C = 112 °C on heating. A ferroelectric-to-relaxor phase transition is verified at T_C by dielectric spectroscopy. Frequency-dependent permittivity is observed in dielectric measurements, revealing relaxor behavior above T_C. Poling the crystal at room temperature does not change T_C, but suppresses the permittivity. Typical ferroelectric hysteresis loop is displayed at room temperature, indicating the ferroelectric nature of the rhombohedral phase.

Keywords:

• single crystals
• ferroelectric
• relaxor
• phase transitions

Additional information

Funding

This work was supported by the United States Office of Naval Research (ONR) [grant number N00014-12-1-1045] and the Natural Science and Engineering Research Council of Canada (NSERC), [grant number DG203773].