Photon coupling-induced spectrum envelope modulation in the coupled resonators from Vernier effect to harmonic Vernier effect

Abstract The Vernier effect and harmonic have attracted ever-increasing interest due to their freely tailored spectrum envelope in tunable laser, modulator, precision sensing. Most explorations mainly focused on configuring two isolated optical resonators, namely the reference resonator. However, this configuration requires a stable resonator guarantee robust readout, posing significant challenge applications. Here, we discover coupled-resonators enabling reference-free modulation address problem. Specifically, all parameters of one theoretically span hypersurface. When couples another one, photon coupling merit an escaped solution from hypersurface, resulting independent reference. We first experimentally verified mechanism coupled air polydimethylsiloxane by inserting semi-transparent 2-mercaptobenzimidazole-modified silver nanowire network. In addition, novel provides new degree freedom reciprocal space, suggesting alternative multiplexing combine more modulations simultaneously. This study facilitates fundamental research multiplexing. More importantly, combination network flexible microcavity progress spectral optoelectronic integration inside resonators.