High fluence KrF excimer laser fabricated Bragg grating in a microfiber

We fabricated a type II fiber Bragg grating in a ∼7.6 μm diameter microfiber, using a KrF excimer laser at a high fluence level of ∼ 1.1 J/cm2 through a phase mask. The proposed microfiber Bragg grating (MFBG) is used to sense the refractive index (RI) of the surrounding medium.