Meander-type wavelength demultiplexer with weighted coupling

An experimental and theoretical investigation of meander-type wavelength demultiplexers with weighted coupling is reported. Numerical simulations have been performed combining a two-dimensional finite difference analysis and a suitably developed coupling mode method. Devices have been realized based on rib waveguides in GaInAsP/InP with filter center wavelengths around 1.3 mu m. With weighted coupling the sinc2( lambda )-type transmission characteristics of standard meander couplers change and the sidelobes of the latter devices are efficiently suppressed. The authors further show the determination of optimum weighted coupling for wavelength filters meeting given requirements with respect to channel separation, maximum allowable crosstalk, and total device length.