Symmetry-breaking dynamics of the modulational instability spectrum

Abstract

We demonstrate in an optical fiber that third-order dispersion yields an unexpected symmetry-breaking dynamics of the modulational instability spectrum. It is found in particular that this spectral asymmetry does not smoothly and monotonically increase when approaching the zero-dispersion wavelength. Instead, it exhibits several local extrema and it can even be reversed at a particular dispersion value. We interpret this behavior as resulting from interactions between dispersive waves and solitons generated from modulation instability.

Fermi-Pasta-Ulam Recurrence in Nonlinear Fiber Optics: The Role of Reversible and Irreversible Losses

“…[23], or in the framework of noise-seeded modulation instability (MI) fiber systems reported in Ref. [22], where random initial conditions prevent the amplification of a single resonant mode (a monochromatic wave in optics) that is crucial in the FPU concept [1]. We show here that the system is capable of recovering its initial state by reversing the energy-flow transfers, which was not the case either in Ref.…”

“…The DSF is the same as in Ref. [22]. The combined power of the pump and the signal launched into the fiber is 27.7 dBm, and the difference between the pump and the signal is 11 dB.…”

“…As a consequence, MI spectra, with the width being inversely proportional to the secondorder dispersion, will be broadened, and it will no longer be possible to consider the dispersion over the whole spectral span to be constant. It will thus be necessary to account for the TOD term, as in other studies in nonlinear fiber optics related to MI [22,24,25] in the low-dispersion region of optical fibers.…”

“…If the dispersion cannot be considered to be a constant over the spectrum, the TOD term must be taken into account [21][22][23][24][25][26][27][28]. This higher-order term strongly modifies the dynamics of nonlinear systems by making them convectively unstable [21].…”

“…This higher-order term strongly modifies the dynamics of nonlinear systems by making them convectively unstable [21]. In optical fibers, it leads to the nonlinear symmetry breaking of parametric processes [22][23][24]28], to the generation of Cherenkov radiations (CRs) by solitons [29], which are one of the key elements of supercontinuum generation [30,31], and, in extreme cases, to turbulent dynamics [32,33].…”