Impulsively excited Surface Phononic Crystals: A route towards novel sensing schemes

The application of all-optical time resolved techniques to nanostructured Surface Phononic Crystals enables the generation and detection of hypersonic frequency surface acoustic waves up to 50 GHz, with great potential for breakthroughs in nanometrology and sensing applications. Here we review the advances in this field both in the theory and experiments, focusing on the progress in non-destructive ultrathin films nanometrology and the promise of dramatically increasing mass sensors sensitivity due to enhanced acoustic wave surface confinement.