Microring resonator for WDM filter applications

Microring resonator (MRR) based optical devices using Silicon-on-insulator (SOI) waveguides are enabling technology. Using multiple microring resonators, very wide free spectral range (FSR) can be obtained. Design and analysis of optical filter using five microring resonators, i.e., pentuple microresonator has been carried out with the help of delay line signal processing and Mason´s gain formula. An FSR of approximately 4007 THz and a crosstalk of -60 dB have been obtained. The group delay and resulting dispersion characteristics have been investigated. FSR expansion has been achieved using Vernier principle. These CMOS-compatible integrated optic devices are capable of accommodating possibly a large number of WDM channels.