S-Matrix Analysis of Dense Wave-division Demultiplexer Based On Add/drop Ring Resonators Structures

In this work, an add/drop micro ring resonator is used to demultiplex eleven frequency lines having a separation of 200 GHz, which are provided by a frequency comb generator. The design of the Si
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TriPleX waveguide structure used for this aim is reported. The waveguide width is 2.2 μm and the heights of the two stacks are 100 and 175 nm for lower and upper layers, respectively. The central frequency of the eleven channels is 193.3 GHz. The ring radii ranges from 40 to 56 μm with the worst crosstalk of 27.23 dB. The validation of the design is executed by FDTD simulation and the S-matrix technique to get the overall response of each ring resonator. The main specifications are set to achieve 3 GHz bandwidth for each channel, reduce the crosstalk between channels, and minimize the radiation losses generated by the rings.