Compact Wavelength Demultiplexer Structure Based on Side-Coupled Cavities

A novel structure based on a side-coupled cavity for optical wavelength demultiplexing is proposed and demonstrated numerically by using the two-dimensional finite element method. It is found that the transmission wavelength of each channel can be tuned by adjusting the geometrical parameters of the structure and the material filling the side-coupled cavity. Moreover, by introducing a reflection nanocavity, the value of the transmitted-peak can be improved significantly. The results of theoretical analysis and simulation are well consistent with each other.