Barium Titanate (BaTiO3)

Publisher Summary It is noted that the barium titanate (BaTiO3) crystal is ferroelectric at room temperature. The crystal structure is perovskite, cubic above the Curie temperature, and tetragonal below the Curie temperature. At room temperature, the a axis is longer than the a axis by 1%. Practically all the barium titanate samples are fabricated by either the flux-grown or the melt-grown method. The lower Curie temperature of flux-grown barium titanate is believed to be a result of the higher impurity content, which also affects the optical constants. The increasedinterest in barium titanate is mainly due to its photorefractive properties and other associated effects and applications, such as phase conjugation, volume holography for optical storage, two-beam coupling, and optical computing. The ultraviolet data obtained is the result of Kramers-Kronig (K-K) analysis of reflectivity measurement on unpoled multiple-domain samples. They represent a certain weighted average of the optical constants for the ordinary ( o ) and extraordinary ( e ) rays.