Bragg reflection grating waveguide

Bragg reflection waveguides (BRW) are non-conventional optical guides in which optical confinement is achieved via periodic set of grooves or stratified media along the guiding path. BRW may also serve as optical filters, because of spectral discrimination of the guiding process. A novel UV laser ablation technique was used in this thesis to fabricate periodic metal-clad polymeric waveguides. Spin-on technique was applied to fabricate the waveguide core on glass substrates, evaporation of metal film and selective ablation process defined the optical guides. Various periodicities have been fabricated and the near field patterns have been measured to compare the different guiding confinement properties. Two techniques for deposition of the polymeric layer have been assessed: spin-on and plasma polymerization. The latter, though being very promising, did not produce a satisfactory yield. Finally, a bend in the waveguide has been fabricated and measured. Good optical confinement has been achieved in the waveguide with the near field patterns becoming narrower when the number of confining structures was increased from two to ten.