Crystal Plane Dependence of Giant Piezoelectricity in Pb[(Zn1/3Nb2/3)0.91Ti0.09]O3 Single Crystals

Abstract

Pb[(Zn 1/3 Nb 2/3 ) 0.91 Ti 0.09 ]O 3 single crystals with various crystal planes were evaluated regarding electromechanical coupling factor of k 31 mode and piezoelectric d 31 constant. Although these values depended on their crystal planes, the giant k 31 and d 31 were obtained in the case of the (100) crystal plane poled along [001] of the original cubic direction. The dielectric constant at room temperature increased with the time in the crystal of (110) plane, while the dielectric constants of the crystals with (100) and (111) planes were unchanged. The crystal plane dependence of ferroelectric properties and their aging characteristics could be explained by the relationships between the directions of the polarization axes and poling field. The bipolar pulse field dependence of k 31 and d 31 were also investigated in comparison with the DC poling field dependence. The giant k 31 and d 31 were obtained in the crystal of (100) plane by the bipolar pulse poling as well as by the DC poling.