Self-sustained coherent phonon generation in optomechanical crystals

Trabajo presentado a la Conferencia Española de Nanofotonica (Spanish Nanophotonics Conference) celebrada en Valencia del 20 al 22 de junio de 2016.Miniaturized self-sustained coherent phonon sources, also known as “phonon lasers”, are interesting for applications such as mass-force sensing, intra-chip metrology and intra-chip timekeeping among others. We will review several mechanisms and techniques that can drive a mechanical mode into the lasing regime by exploiting the radiation pressure force in optomechanical cavities. We will specifically focus on a novel and efficient strategy for achieving the “phonon lasing” regime in optomechanical (OM) crystals using the radiation pressure as the driving force of the motion. The mechanism is based on a self-pulsing limit cycle, which is a spontaneous process triggered within the optical cavity that modulate the intracavity radiation pressure force in resonance with a mechanical mode. Selfsustained mechanical oscillations of modes up to 0,2 GHz are achieved if one of the low harmonics of the modulated force is resonant with a mechanical eigenstate. We will discuss how it will be possible to further speeding up of the self-pulsing dynamics to reach the GHz regime, where the lack of good quality and miniaturized sources is a severe issue.Peer Reviewe