Polarization-Insensitive Four-Channel Wavelength-Division (de)Multiplexer Based on Cascaded Mach-Zehnder Interferometers with Adiabatic Couplers

A polarization-insensitive $1\times 4$ channel wavelength (de)multiplexer based on cascaded asymmetric Mach-Zehnder in-terferometers (AMZIs) is proposed. By utilizing the polarization-insensitive adiabatic 3-dB splitters and waveguides, the wave-length division (de)multiplexer could work for both transverse electric and transverse magnetic polarizations. Simulation results show that the designed device has a 3-dB bandwidth of 3.21 nm for dual polarizations, and the polarization dependent losses are 0.0057 dB for all four channels.