Phononic microresonators coupled by surface acoustic waves

International audienceThe implementation of scalable phononic circuits has become an appealing prospect in view of increasing the versatility of electro-acoustic devices for radio-frequency signal processing. Recent demonstrations have made convincing steps towards this objective by proposing phononic architectures inspired by photonic integrated circuits or combining the rich dynamics of micro- and nano-electromechanical (M/NEMS) resonators with propagating elastic waves.In this work, we propose to exploit the interaction between surface acoustic waves (SAW) and locally-resonant, micron-scale mechanical resonators in order to achieve coherent driving of the resonator motion with SAW and, reciprocally, to control the elastic energy distribution at a deep sub-wavelength scale. Optical measurements by laser scanning interferometry allows retrieving both the resonator frequency response and mode shape, hence enabling direct observation of the vectorial nature of the interaction. We investigate the proposed physical system both in the linear and non-linear regimes and reveal that the elastic field behavior can be further controlled through resonator-to-resonator coupling, leading to a variety of interaction schemes. The proposed devices illustrate the potential of SAW-based architectures for the implementation of high-frequency phononic-NEMS circuits.