Dynamics of cascaded resonant radiations in a dispersion-varying optical fiber

Temporal solitons propagating in the vicinity of a zero-dispersion wavelength in an optical fiber emit phase-matched resonant radiations (RRs) as a result of perturbations due to higher-order dispersion effects. These RRs propagate linearly and they usually rapidly spread out in time, thus having a very low peak power. Here, we show that the use of an engineered dispersion-varying optical fiber allows us to induce a completely new dynamics, in which a new physical mechanism-cascade of RRs-is discovered. It is explained by the fact that the RR is temporally recompressed thanks to the change of dispersion sign induced by the varying geometry along the fiber. In addition, we report the experimental evidence of physical processes that had remained unobserved experimentally so far, such as the emission of multiple RRs from a single soliton and the generation of a 500 nm continuum exclusively composed of polychromatic RRs. (C) 2014 Optical Society of America