Frequency Combs and Stochastic Responses in A Curved Microbeam Featuring 2:1 Internal Resonance

In this paper, we investigate the generation of frequency combs, dense equidistant spectral lines, in a MEMS device featuring a 2:1 internal resonance. We have observed the emergence of two distinct patterns of frequency combs and a chaotic regime under different excitation conditions. We have conducted an in-depth analysis of these novel dynamic phenomena, proposing a mechanism centered on the competition of two types of nonlinear wave mixing processes in the parametric excitation, resulting in a transition in the response state. Moreover, we have analyzed the stochastic dynamics of the peculiar comb-like responses within the chaotic region. This work further delves into the intricate dynamic behaviors of a modal interaction device within the frequency comb regime and provides guidance for the design of frequency comb generators based on micro-electromechanical systems (MEMS).