Evidence for Simultaneous Growth and Saturation Mechanisms in Phononic Frequency Combs

Phononic frequency combs refer to mechanical vibrations which are evidenced by a series of equidistant spectral lines. Such combs contain signals oscillating at drive frequency and resonant frequency, among other equidistant spectral lines. This paper shows that there exist specific growth and saturation mechanisms for each comb line and the nature of such mechanisms can be different for variant comb dynamical pathways. The fundamental understanding of such contrasting growth and saturation mechanisms is directly relevant to the engineering of either single tone self-sustained oscillation at resonant frequency or broadband frequency comb spectrum.