Lumerical-Based SiN Half-Band FIR Maximally Flat-Top Optical Filter with Low Insertion Loss and High Extinction Ratio at 193 THz

This paper presents a maximally flat-top half-band FIR optical filter on a silicon nitride (SiN) platform at 193 THz. Using a cascaded Mach-Zehnder Interferometer (MZI) topology simulated in Lumerical INTERCONNECT, MODE, and FDTD, the filter achieves insertion losses of 0.1349 dB and 0.1761 dB with extinction ratios of 18.317 dB and 23.002 dB for Channel-A and Channel-B, respectively, under realistic S-parameter conditions.