Enhanced Piezoelectric Property of Barium Titanate Single Crystals with Engineered Domain Configurations

Abstract

Piezoelectric properties of barium titanate single crystals were investigated at room temperature as a function of crystallographic orientation. When a unipolar electric field was applied along [001], its strain vs electric-field curve showed a large hysteresis, and finally barium titanate crystal became to single-domain state with piezoelectric constant d 33 of 125 pC/N over 20 kV/cm. On the other hand, electric-field exposure below 6 kV/cm along [111] resulted in a high d 33 of 203 pC/N and a hysteresis-free strain vs electric-field behavior, which suggested the formation of an engineered domain configuration in a tetragonal barium titanate crystal. Moreover, when an electric field over 6 kV/cm was applied along [111], two discontinuous changes were observed in its strain vs electric-field curve. In situ domain observation and Raman measurement under an electric field suggested an electric-field-induced phase transition from tetragonal to monoclinic at around 10 kV/cm, and that from monoclinic to rhombohedral at around 30 kV/cm. Moreover, in a monoclinic barium titanate crystal, electric-field exposure along [111] resulted in the formation of another new engineered domain configuration with d 33 of 295 pC/N.

Domain engineering of the transverse piezoelectric coefficient in perovskite ferroelectrics

“…A longitudinal piezoelectric coefficient of 203 pC/ N was reported by Wada et al for 3T ͗111͘ C -poled tetragonal barium titanate ͑BaTiO 3 ͒. 8 This is more than twice the single-domain value ͑d 33 =90 pC/N͒ measured along the ͗001͘ C polar axis. 13 Many authors have tried to ascertain the origins of the elevated piezoelectric coefficients in domain-engineered crystals.…”

“…Following the rediscovery of their very high piezoelectric coefficients for rhombohedral or orthorhombic compositions oriented along the nonpolar ͓001͔ C ͑C: pseudocubic͒ direction, 1 much work has concentrated on the concept of domain engineering 2 not only in these materials [3][4][5][6][7] but in simpler perovskite crystals as well. [8][9][10] A good definition of "domain engineering" is that given by Bell: 2 A domain-engineered crystal is one which has been poled by the application of a sufficiently high field along one of the possible polar axes of the crystal other than the zerofield polar axis, creating a set of domains in which the polarizations are oriented such that their angles to the poling direction are minimized. In a perovskite material there are therefore three possible sets of poling directions ͗111͘ C , ͗101͘ C , and ͗001͘ C ͑if monoclinic phases are ignored͒.…”

Domain-size dependence of piezoelectric properties of ferroelectrics

“…Many devices such as ultrasonic transducers and piezoelectric actuators make use of this property 2 . Recently, there has been considerable interest in this field due to the observation of a giant piezoelectric response if the applied field is along a non-polar direction 3,4 . It is believed that this "superpiezoelectric" response is due to the symmetry change caused by a rotation of the polarization towards the direction of the applied field 5 .…”

Broadband inelastic light scattering of a relaxor ferroelectric 0.71Pb(Ni1∕3Nb2∕3)O3-0.29PbTiO3

“…6 In the case of polarization switching in barium titanate, the 180°d omain can switch faster than the 90°domain because no strain is induced during switching. 19 In other words, the energy barrier of 180°domain switching can be much smaller than that of the 90°domain switching. A similar situation occurs for the switching of polarization of PNRs in 0.71PNN-0.29PT, and two relaxations in the dipole switching can be considered in PNRs.…”