Indium oxide overlay gratings realised on glass waveguides using excimer laser ablation

Description/Abstract

Relief gratings overlaid on optical waveguides may be used as high-extinction ratio wavelength filters with applications in integrated optics and optical communications. Cross-patterned, high contrast relief grating waveguide structures may potentially perform as 2-D photonic band gaps if properly designed and fabricated. A new waveguide grating design process which relies on a novel grating patterning method and new materials will be presented in this paper. This design consists of the combination of a potassium ion-exchanged singlemode channel waveguide with a high-index film (InOx) overlaid on its upper surface [1]. The high-index overlayer is deposited over a part of the waveguide length. A relief grating is patterned on the InOx layer using 248nm interferometric excimer laser ablation [2].