The Potsdam astroComb (POCO) Part I: Mode crossing effect in feedback resonators

• DOI: 10.48550/arxiv.2311.13505
• Publication Date: 2023-01-01
• Authors: D. Bodenmüller; Kalaga Madhav; Martin M. Roth
• Keywords: Path length; Mode (computer interface); Optical path; Waveguide

We investigate theoretically and experimentally the mode interaction in an integrated Silicon Nitride (Si3N4) microring resonator with interferometric coupling realized by a feedback loop as adjustable optical path length connecting ring to bus waveguide at two sections. From transmission spectra recorded different lengths, resonances, 1596.5~nm 1570.5~nm, were selected for detailed investigation. Both resonances show possibility of adjusting resonance width depth. However, around first also effect interaction. This is well captured theoretical model, from which we can derive rate $3.4~\textrm{rad}~\textrm{ns}^{-1}$.