我们报道了用高分辨布里渊散射,确定0.67Pb(Mg 1/3Nb 2/3)O3-0.33PbTiO3单晶中的弹性、压电和介电常数.所有的实验数据都是在一块沿[001]方向的极化的单晶样品上获得的.我们实验中得到的这些常数的数值和以往超声共振技术获得的数值相似.我们还研究了压缩模和剪切模在(010)和(001)平面内的方向依赖性.TA1和TA2模式的强度对散射角度有很强列依赖性.在散射角度为45°～65°内,一个新的峰出现在～18 GHz附近.它可能与晶体中的微观不均匀性或者局域微结构相关.%We report the determination of the complete set of elastic, piezoelectric and dielectric constants of 0.67PMN-0.33PT crystal by using high-resolution Brillouin scattering in which all experimental data were collected from only one [001]-poled crystal sample. The values of determined constants are similar to those previously determined from four crystal samples by using a hybrid method combining both ultrasonic and resonant techniques. The directional dependence of the compressional and shear modulus of the crystal in (010) and (001) planes were investigated. The scattering intensities of TA1 and TA2 modes show a strong dependence on the scattering angle. A new feature appears at the low frequency side (～18 GHz) between 45°～65° scattering angles and it may be related to the microheterogeneity or to a local microstructural change and some defect states in the crystal.
展开▼
