Enhancement of Energy Exchange Rate in Mode-Coupled MEMS for Supercontinuum Frequency Combs and Injection Locking

This paper reports the design principle for the energy exchange rate in mode-coupled MEMS resonators and the induced micromechanical frequency combs (MFCs). The coupling enhancement design increases the energy exchange rate and widens the comb spacing, allowing the adjacent comb clusters to overlap and then precisely align via injection locking, forming a supercontinuum frequency comb with noise-squeezed comb lines. The dynamic principle lies in the replacement of the typical quasi-periodic vibration of MEMS combs by periodic motion, significantly reducing the fluctuations in the phase offset between the two coupled modes, leading to improved long-term frequency stability.