Fiber Bragg gratings with various chirp profiles made in etched tapers

Abstract
We have studied, both theoretically and experimentally, fiber Bragg gratings with a number of different chirp profiles. These chirp profiles can easily be achieved by a recently demonstrated technique involving a taper of desired profile etched into the cladding of a fiber. The performances of gratings with linear, quadratic, periodically modulated, and step-chirp profiles are analyzed numerically. The versatility of the technique was demonstrated when linearly and quadratically chirped gratings were made as examples of continuous chirp, and gratings with step chirps were made as examples of discontinuously chirped structures.