A novel integrated method enabling the study of nano-structured materials is presented, which is based on the imaging and monitoring of the spatiotemporal evolution of short-pulse-laser-generated Surface Acoustic Waves (SAWs). The method combines a 3D whole-field imaging laser interferometric experimental diagnostic technique and Finite Element Analysis (FEA) theoretical simulations.
The experimental technique utilizes a single-longitudinal mode nanosecond laser source for both the generation and recording of the SAWs. It provides nanometer transverse spatial resolution vertical to the material surface, via direct whole-field imaging with nanosecond temporal resolution, thus avoiding extensive surface scanning. The theoretical model simulates the laser-material interaction as well as the generation and propagation of SAWs. FEA offers substantial insights into the materials’ micro-elastomechanic behavior providing detailed information for the spatiotemporal evolution of SAWs.
This integrated method is here applied on simple material samples consisted of thin metal films coated on dielectric substrates. The results validate the applicability and the potential of the proposed method in the area of nanostructured materials micromechanical characterization.
(EN)
