Abstract

We report about a thermal regeneration of fiber Bragg gratings written in photosensitive fibers without hydrogen loading and with the use of UV nanosecond laser pulses. We observe a complex regenerative process which indicates a secondary grating growth in an optical fiber by thermal activation. This process leads to an increased temperature stability of the gratings which differs from the commonly known types of gratings. We analyze the evolution of the average refractive index and of the refractive index modulation.

© 2010 Optical Society of America