Role of the 1D optical filamentation process in the writing of first order fiber Bragg gratings with femtosecond pulses at 800nm [Invited]

摘要

The role of the optical filamentation of ultra-short infrared pulses at 800nm in the inscription of highly reflective and low loss fundamental order fiber Bragg gratings is investigated. The onset of the filamentation process is first evidenced through the observation of the spectra of both supercontinuum generation and plasma emission as well as through the precise measurement of the plasma-induced refractive index change. Typical samples of FBG obtained with this approach are presented.