Z-domain modelling and performance analysis of high contrast grating embedded micro-optical double ring-resonance filters

The optical ring resonance filter design using different double-ring structures with an inserted BG is proposed in the present article. A high-index contrast grating is integrated with the filter models and is configured as an individual cell transfer function. Each double-ring design is embedded with a grating element, and by transforming it into an SFG representation from the waveguide layout, the Z-domain modelling is performed. The Z-transform approach is an effective tool in modern-day optical communication, which also finds its use in spectral analysis. The establishment of the optical ring resonance is also achieved, and the Opti-FDTD software served the purpose. The frequency responses of the filters are obtained in the MATLAB environment. The spectral profiles of the filters are almost identical and obtain an FSR bandwidth of 27.09 THz, which is a great advantage. Other than the FSR bandwidth, performance parameters like transmission peak, sidelobe magnitude, and SMSR magnitude are also measured.