Bragg grating inscription in BDK-doped PMMA optical fiber using 266 nm pulsed laser

In this work, we reported highly reflective polymer optical fiber Bragg gratings (POFBGs) in poly(methyl methacrylate) (PMMA)-based polymer optical fibers (POFs) by means of a 266 nm pulsed laser and phase mask technique. Fiber Bragg gratings (FBGs) were inscribed with a single pulse up to 3.7 mJ. After post-annealing, a stable refractive index change up to 4.2×10^-4 was obtained. The behavior may mainly be attributed to the movement of initiating radicals arising from BDK under UV irradiation.