Influence of 180° domains on ferroelectric properties of BaTiO3 single crystal

Mechanical poling was applied to a BaTiO3 single crystal grown by the top-seeded solution growth (TSSG) method to remove its 90° domain walls, and then four-step electrical poling was applied to rearrange the 180° domain configuration. In each of these steps, the dielectric constant (from 50 kHz to 10 MHz) was measured by using an impedance analyzer, and the 180° domains were observed by the etching method. The dielectric spectra were confirmed to vary with rearrangement in 180° domain configuration. Dielectric constant εc in the 〈001〉 direction was 130 at 100 kHz and 58 at 10 MHz. Dielectric constant εa in the 〈100〉 direction was 4700 at 100 kHz and 1900 at 10 MHz.