2021/01/26 by Laura Mercadé, Karl Pelka, Roel Burgwal +3
Physics and Astronomy · #physics.optics
paper · pdf · doi:10.1103/physrevlett.127.073601
published as Phys. Rev. Lett. 127, 073601 (2021)
arxiv created 2021/01/26 · arxiv updated 2021/08/18
Dynamical radiation pressure effects in cavity optomechanical systems give rise to self-sustained oscillations or `phonon lasing' behavior, producing stable oscillators up to GHz frequencies in nanoscale devices. Like in photonic lasers, phonon lasing normally occurs in a single mechanical mode. We show here that phase-locked, multimode phonon lasing can be established in a multimode optomechanical system through Floquet dynamics induced by a temporally modulated laser drive. We demonstrate this concept in a suitably engineered silicon photonic nanocavity coupled to multiple GHz-frequency mechanical modes. We find that the long-term frequency stability is significantly improved in the multimode lasing state as a result of the phase locking. These results provide a path towards highly stable ultra-compact oscillators, pulsed phonon lasing, coherent waveform synthesis, and emergent many-mode phenomena in oscillator arrays.