Acoustoelectric effects in reflection of leaky acoustic waves from LiTaO_3 crystal surface coated with metal film

摘要

The strong variations in amplitude and phase of leaky acoustic wave excited on one surface of YX lithium tantalate crystal plate and reflected from the opposite parallel surface have been observed during thermal evaporation of copper film onto the reflection surface. These variations are caused by the acoustoelectric interaction in the reflection region, and they are described in terms of surface acoustic wave velocity and attenuation dependence on the film sheet conductivity. The electromechanical coupling constant value of 5% has been extracted from amplitude measurements, and that of 4% from the phase measurements.