Multichannel optical waveguides formed by periodic microcavities

We demonstrate light propagation in a novel type of optical waveguide, which consisting of periodically arrayed dielectric particles. Advantages provided by this waveguide are that dynamic optical interconnection can be realized and that a multichannel waveguide is easily formed. To fabricate the system of periodic micro cavities, we used polystyrene- latex particles that have a uniform size of 15.6 micrometers . The second harmonic of a Nd:YVO4 laser, the wavelength 532 nm, was introduced to the sample substrate in order to excite the fluorescence of Rhodamine 6G. Some discrete frequencies of fluorescence were selected to agree with the phase matching condition and produce a resonance mode in a microsphere. Part of the energy transferred to the adjacent spheres via evanescent light. Thus, some discrete frequencies of the fluorescence propagated through the microspheres. Since the particles are arrayed symmetrically, the resonance light can propagate in three different directions. The propagating direction can be controlled to regulate the location of a focused spot. In addition, if you illuminate the next microsphere, the excited light propagates in the next line of arrayed microspheres. The assembled microspheres can be taken as a multichannel waveguide.