Non-linear dynamics in opto-mechanical oscillators

Cavity opto-mechanics enabled opto-mechanical oscillators leverage coupling between high quality factor mechanical and optical resonances in a micro-resonator. The inherently high quality factors make such systems susceptible to various non-linearities. This paper presents the first reported experimental demonstration of various non-linear dynamics observed in a silicon opto-mechanical oscillator, and specifies operating conditions required to inhibit these effects. We present four non-linear effects viz. i) oscillations of parasitic mechanical modes, ii) chaotic mechanical oscillations, iii) multi-GHz oscillations driven by two photon absorption, and iv) coherence of the excited mechanical oscillations, similar to optical frequency combs.