On the design of photonic crystal multiplexers

Abstract
We propose a general design methodology for photonic crystal (PhC) diplexers, which is carried out along a filtering T-junction. The diplexer operation is investigated while carefully analyzing the dispersion relations of the three different waveguide channels. All simulations are carried out using the multiple multipole method (MMP), which offers perfect excitation and matching conditions for all waveguide ports involved. The resulting diplexer is highly compact (it covers an area of 13×9 lattice constants) and simple when compared to other PhC diplexer designs.