Acoustic anisotropy of piezoelectric PbB4O7 crystals studied by laser ultrasonics

Acoustic anisotropic properties of PbB4O7 crystals are investigated and dis cussed. The slowness curves of three bulk waves as well as the surface wave s for the plates with different cut directions are calculated by considerin g piezoelectric effects. The theoretical calculations are in agreement with experimental results determined by laser ultrasonic technique. On the othe r hand, the excitation efficiency of surface waves of PbB4O7 crystals is ob tained by calculating the change of the velocities of acoustic surface wave s get from the plates bare and deposited by a thin metal film. The results of this paper can be used for selecting PbB4O7 crystal orientations for des igning the related devices. (C) 2001 Elsevier Science B.V. All rights reser ved.