Observation of multiple stop bands in photonic bandgap structures doped with organic dyes

Intensity enhancement of the optical stop band of a periodic quasicrystalline structure is achieved by infiltrating this structure with a suitable dye, as demonstrated for monodisperse polystyrene beads doped with the organic dye Oil Red EGN. A detailed discussion of the optical properties of the system is given in terms of the Bragg and Snell laws, and constraints concerning the refractive index of the dye, LATEX bead diameter, and quasicrystal lattice are extracted. Following some simple geometrical constraints the opening of the photonic bandgap can thus be tuned.