Proposal of a Coupled-Microring-Based Wavelength-Selective $1\times N$ Power Splitter

A novel wavelength-selective 1 times N power splitter, which consists of a microring and N + 1 couplers, is presented. One coupler is for coupling the light signal from the input port into the microring and the other N couplers are for coupling the signal light from the microring to the output ports. The channels with the resonant wavelength of the microring are dropped and split into N output ports. The critical coupling condition to achieve a high extinction ratio is also given. By appropriately choosing the coupling coefficients for the input/output couplers, it is flexible to have a uniform or nonuniform power splitting as desired.