Open AccessPolarization properties and crystal structures of ferroelectric (Ba,Ca)TiO3 single crystals
Author(s) -
Ryota Imura,
Yuuki Kitanaka,
Takeshi Oguchi,
Yuji Noguchi,
Masaru Miyayama
Publication year - 2014
Publication title -
journal of advanced dielectrics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.38
H-Index - 13
eISSN - 2010-135X
pISSN - 2010-1368
DOI - 10.1142/s2010135x14500039
Subject(s) - font , octahedron , polarization (electrochemistry) , ferroelectricity , supercell , materials science , crystallography , single crystal , pyroelectricity , crystal structure , physics , dielectric , optoelectronics , chemistry , thunderstorm , meteorology , computer science , operating system
We have investigated the spontaneous polarization (P s ) of Ba 1-x Ca x TiO 3 (BCT) by polarization hysteresis measurements using single crystals and by density functional theory (DFT) calculations. Single crystals of BCT (x = 0.07) were grown by a top-seeded solution growth (TSSG) method. The polarization measurements show that the crystals (x = 0.07) have a P s of 26.0 μC/cm 2 , which is slightly small compared with BaTiO 3 (27.3 μC/cm 2 ). Our DFT calculations based on a supercell approach show that Ca atoms are markedly displaced cooperatively with the adjacent Ti atoms along the P s direction. It is suggested that the CaTiO 3 -like octahedral rotation is constructed in the BCT supercell around the Ca atoms, which is the origin of the smaller P s observed for the BCT crystals.