Photonic band gap wavelength multiplexer-demultiplexer

The performance of an optical multiplexer-demultiplexer based on an index-confined photonic band gap waveguide has been investigated. The dropping of electromagnetic waves, having a given frequency band, is realized via a phase-shifted grating obtained by breaking the uniform period sequence to include defect layers. To equalize the channel level, the defects are designed following the Newton binomial coefficients. The selective filtering properties of the proposed structure have been simulated by means of a computer code relying on a bidirectional beam propagation method based on the method of lines.