title: Fabrication of high-reflectivity superimposed multiple-fiber Bragg gratings with unequal wavelength spacing.
abstract: We report the inscription of as many as 10 superimposed Bragg gratings of high reflectivity in a 25-mm segment of fiber. Using hydrogenated boron codoped and germanosilicate fibers, we inscribed 10 superimposed gratings with reflectivities above 80% and 6 superimposed gratings with reflectivities above 98%, respectively. The superimposed gratings had unequal wavelength spacing and were written over a 20-nm wavelength span in the region of 1530 nm. The inscription of each new grating caused an increase in the FWHM linewidth of the existing gratings, while their reflectivity was unaffected.
authors.forename: A
authors.initials: A
authors.lastname: Arigiris
authors.forename: M
authors.initials: M
authors.lastname: Konstantaki
authors.forename: A
authors.initials: A
authors.lastname: Ikiades
authors.forename: D
authors.initials: D
authors.lastname: Chronis
authors.forename: P
authors.initials: P
authors.lastname: Florias
authors.forename: K
authors.initials: K
authors.lastname: Kallimani
authors.forename: G
authors.initials: G
authors.lastname: Pagiatakis