High-resolution imaging of surface acoustic wave scattering

We examine the scattering of surface acoustic waves (SAWs) by single dots, periodic and locally damped two-dimensional dot lattices. Employing the sca nning acoustic force microscope, SAW fields are imaged with nanometer resol ution. We study the influence of a roughly wavelength-sized single dot on S AW diffraction. In order to distinguish between forward- and backscattered components, we insonify the dot with the pump and probe beam under 0 degree s and 90 degrees. We furthermore analyze the SAW diffraction by a regular d ot array. The wave field appears to be localized around the dots. Adding su rface distortions, the regular SAW localization pattern brakes down in the vicinity of the distortion. (C) 2001 American Institute of Physics.