Spectral Talbot effect in sampled fiber Bragg gratings with super-periodic structures

Abstract

Due to the equivalence between an integral multiple of 2pi?and zero in the phase space, a general configuration of sampled fiber Bragg gratings (SFBGs) with super-periodic structures has been introduced and investigated. These super-periodic structures can be used to implement spectral Talbot effect with a large degree of freedom, as long as any one of the three parameters involved in quadratic phase profile is an even number. Then the phase profiles of such SFBGs are analyzed in detail. Although their phase increments are constant or non-constant periodic functions in different cases, theoretical analysis and simulations show that the obtained filtering characteristics are the same. In contrast to uniform SFBGs with identical sampling period, multiplied filtering channels and similar groupdelay characteristic are achieved for these SFBGs with super-periodic structures.