Tunable Coupled-Resonator Induced Transparency Based on Asymmetrical Self-Interference Ring Resonators

Abstract

Tunable coupled resonator induced transparency (CRIT) is observed based on two asymmetrical self-interference ring resonators (SIRRs). The phase shift of the left feedback arm will regulate the output CRIT lineshape, whereas the right FA does not influence the output lineshape. The transmission spectra of the left SIRR will be greatly reshaped with different cross-coupling coefficients, this characteristic is of great use both for optical sensing and designing output lineshape. Instead of adding ring resonators or tuning the uncontrolled multimodes of the whisper gallery resonator, we realize two transparency windows via changing the cross-coupling coefficients of couplers, which provides a convenient and controllable approach for the multichannel filter in optical devices. Moreover, the number of transparency window can be extended via adding more resonators. The proposed structure provides a potential application in the optical filter, optical sensing, slow light, and optical storage.