Strong Bragg Gratings in Highly Photosensitive Photo-Thermo-Refractive-Glass Optical Fiber

Abstract

International audienceA new type of photosensitive fiber is demonstrated. Long lengths (>100 m) of coreless optical fiber are fabricated from highly photosensitive photo-thermo-refractive glass. A minimum loss of <;2 dB/m is measured. A holographic technique using low power near-UV two-beam interference patterns is applied to record strong and robust Bragg gratings inside the fiber. The gratings show no degradation when heated up to 425 °C for several hours