Role of coexisting tetragonal regions in the rhombohedral phase of Na0.5Bi0.5TiO3-xat.%BaTiO3 crystals on enhanced piezoelectric properties on approaching the morphotropic phase boundary

• Published in: Applied physics letters Vol. 100; no. 1
• Main Authors: Yao, Jianjun, Monsegue, Niven, Murayama, Mitsuhiro, Leng, Weinan, Reynolds, William T., Zhang, Qinhui, Luo, Haosu, Li, Jiefang, Ge, Wenwei, Viehland, D.
• Format: Journal Article
• Language: English
• Published: 02-01-2012
• ISSN: 0003-6951; 1077-3118
• DOI: 10.1063/1.3673832

The ferroelectric domain and local structures of Na0.5Bi0.5TiO3-xat.%BaTiO3 (NBT-x%BT) crystals for x = 0, 4.5, and 5.5 have been investigated by transmission electron microscopy. The results show that the size of polar nano-regions was refined with increasing xat. %BT. The tetragonal phase volume fraction, as identified by in-phase octahedral tilting, was found to be increased with BT. The findings indicate that the large electric field induced strains in morphotropic phase boundary compositions of NBT-x%BT originate not only from polarization rotation but also polarization extension.