Abstract
X-ray diffraction, dielectric constant measurement, and microscopic observation were carried out on antiferroelectric PbZrO3 under high pressures up to78, 22, and 48 GPa, respectively, at room temperature. By x-ray diffraction analyses, it was clearly recongnized that an orthorhombic ambient-pressure phase transforms to a monoclinic phase at around 37 GPa, and then again to a slightly different monoclinic phase above 75GPa. A large anomaly in the dielectric constant was observed at around 19 GPa, which strongly suggests the appearance of ferroelectricity in PbZrO3 at high pressure. Optical observation showed that the color changes from pale yellow into thin red at around 19 GPa and then further to black at around 37 GPa. The former change is associated with the dielectric anomaly and the latter with the phase transition to a monoclinic phase discovered by x-ray diffraction.
