A wavelength demultiplexing structure based on plasmonic MDM side-coupled cavities

A structure based on plasmonic metal-dielectric-metal (MDM) side-coupled cavities for optical wavelength demultiplexing is proposed and numerically simulated. The structure consists of several side-coupled resonant cavities with different lengths, which plays roles in selecting different wavelength transmission bands. Both analytical and simulation results reveal that the selected demultiplexing wavelength of each port has linear and nonlinear relationships with the length of the corresponding MDM side-coupled cavity, overlap length, and gap width.