Here is a set of examples of photonic band gap structures.

Project item 'lambdascan' shows how fimwmave/fimmprop-3d 
may be used to find a photonic band gap of a given lattice.
Follow the online notes in this project for detailed 
instructions.

The project items lattice2W1,....,lattice2W7 are
examples of light guided in channels in the PBG.
These show in particular the bidirectional capabilities 
of fimmprop!