Resonant Excitation-Induced Nonlinear Mode Coupling in a Microcantilever Resonator

The nonlinear dynamics of microelectromechanical resonators has recently garnered significant attention for their potential use in high-precision detection and information processing. In this paper, we report resonant excitation as a powerful tool for generating nonlinear mode coupling in a cantilever microresonator. It is discovered that resonant driving at its second flexural mode ${f}_{2}$ under moderate driving amplitude gives rise to blue and red sidebands due to mode coupling between the fundamental mode and the second flexural mode. Detuning the driving frequency enables a continuous shift in the frequencies of the blue and red sidebands with a frequency span of 220 Hz. Further increase in the drive amplitude at ${f}_{2}$ mode splitting, and broadband acoustic frequency comb with a frequency span exceeding 500 kHz. Our findings pave the way towards parametric control based on injection locking for manipulating multimode mechanical resonator systems.