Dammann fiber Bragg gratings and phase-only sampling for high channel counts

Abstract

Fiber Bragg gratings with phase-only superstructure ("sampling") are shown to greatly increase the reflectivity of large channel count designs. Grating fabrication is facilitated by the standard mask side-writing technique, where the entire sampling pattern is included in the phase mask. A novel phase sampling design based on binary Dammann gratings as well as continuous phase sampling functions is demonstrated and exhibits excellent channel-to-channel uniformity.