Bragg Gratings Written in Tapered Solid-Core Photonic Crystal Fibers

Fiber Bragg gratings are very useful in many applications. This is why a higher control of their properties is desirable. Therefore, a grating preprocessing technique, based on the dependence of the index guided photonic crystal fiber (IG-PCF) properties on their structural parameters, is proposed allowing a higher control of the Bragg wavelength. Using the proper combination of thermo-mechanical IG-PCFs tapering and ultraviolet photoinscription methods, it is possible to develop new optical fiber devices. Their effectiveness is demonstrated by comparison with the results on single-mode fiber. Finally, to demonstrate the feasibility of the technique, a wideband chirped Bragg grating is fabricated.