research
High reflectivity Bragg gratings fabricated by 248nm excimer laser holographic ablation in thin Ta<sub>2</sub>O<sub>5</sub> films overlaid on glass waveguides
- Publication date
- Publisher
Abstract
Relief Bragg grating reflectors inscribed on channel waveguides may be used in optical communications as add-drop wavelength multiplexers, gain-flattening filters, distributed feedback laser mirrors, or in sensing technology as high sensitivity devices for precise monitoring of chemical or biomedical processes. We present strong Bragg grating reflectors in Ta2O5 thin oxide films overlaid on potassium ion exchanged channel waveguides in BK-7 glass, inscribed using 248nm excimer laser
holographic ablation. The grating pattern was created employing two-beam
interference using a modified Mach-Zehnder interferometric cavity and the output of a
narrow-lined injection cavity 248nm excimer laser. The experimental data presented
are divided into two sections: the first section refers to the study of the grating
ablation process of thin Ta2O5 films with respect to the exposure conditions; and the second focuses in the implementation of those relief grating in functional waveguide devices