A numerous techniques for noncontact measurements of acoustic waves and vibration parameters using AFM [1,2] or STM [3,4] have been developed the last years. It has been demonstrated that nanoprobe systems enable high-resolution measurement of surface, longitudinal, and shear acoustic waves. We present combined system that includes a pulse laser as a source of surface acoustic waves and two tunneling probe to detect phase and amplitude of the acoustic waves in GHz frequency range. This approach makes it possible to measure parameters of the acoustic waves in nanomaterials and to calculate their mechanical properties including elastic modulus and shear modulus. Also it is possible to detect the onset of plastic creep during nanoscale surface modification. A theoretical model embracing acoustics measurements using tunneling phenomena is described. Laboratory experiments have displayed results that are in agreement with those obtained from theoretical model.
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[4] P.U. Voigt and R. Koch, J. Appl. Phys. 92, 7160 (2002).
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