The recent results about the fabrication and characterization of Long Period Gratings (LPGs) in different pure silica opticalfibers by means of Electric Arc Discharge (EAD) technique are reported in this work. Nowadays, LPG in standard fiberrepresents a unique platform for physical, chemical and biological sensing whereas specialty optical fibers permit to extendthe use of fiber optic technology to unconventional applications. For instance, pure silica fibers are appealing in highenergy applications. Here, we take into consideration two fibers with pure-silica core having significant differences inphysical and geometrical design. The first one presents a micro-structured pure-silica cladding, photonic crystal fiber, andthe second one shows a solid Fluorine-doped cladding. EAD leads to a point-by-point LPG inscription, due to localizedtapering of the transversal size of the core and cladding regions along the fiber, and to changes of the silica refractive indexdue to the stress relaxation induced by local hot spots. The aim of the work is to identify an appropriate “recipe” for eachfiber, to fabricate LPGs with strong and narrow attenuation bands and trivial power loss. Indeed, a proper combination ofarc power and duration, as well as fiber tension, allows for the appropriate core and cladding modulation and thus for thedesired LPG spectral features. The sensitivity characteristics towards surrounding refractive index (SRI) and temperaturechanges of these LPGs are also investigated.
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