The statistics of the reflection spectrum of a short-correlated disordered fiber Bragg grating are studied. The averaged spectrum appears to be flat inside the bandgap and has significantly suppressed sidelobes compared to the uniform grating of the same bandwidth. This is due to the Anderson localization of the modes of a disordered grating. This observation prompts a new algorithm for designing passband reflection gratings. Using the stochastic invariant imbedding approach it is possible to obtain the probability distribution function for the random reflection coefficient inside the bandgap and obtain both the variance of the averaged reflectivity as well as the distribution of the time delay of the grating.
© 2008 Optical Society of America
Fiber Optics and Optical Communications
Original Manuscript: June 10, 2008
Revised Manuscript: August 20, 2008
Manuscript Accepted: August 25, 2008
Published: October 15, 2008
Stanislav Derevyanko, "Design of a flat-top fiber Bragg filter via quasi-random modulation of the refractive index," Opt. Lett. 33, 2404-2406 (2008)