Abstract

It is well known that high order dispersive perturbations induce optical solitons to emit resonant radiaton (RR) in the normal dispersion regime [1]. More recently, it has been experimentally reported [2] and theoretically demonstrated [3] that the RR can be shed also in the anomalous dispersion regime, when the pump is a shock wave. In axially varying fibers, the generation of RR may lead to even much more complex scenarios due to the design flexibility offered by these waveguides [4]. We report here striking evidence that periodicity of the dispersion is responsible for the parametric excitation of RR at multiple resonant frequencies. They are generated according to the quasi-phase-matching relation $D({\omega }_{RR})-k_{nl}-=\frac{2\pi }{\Lambda }m$, where D(ω) is the average dispersion in the reference frame of the pump, k_nl is the nonlinear wavenumber and Λ is the period.

© 2015 IEEE