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Featured Application: Supercontinuum generation in novel infrared fibers from high-repetition-rate femtosecond mode-locked laser pulses provides mid-infrared radiation with very attractive features such as high coherence and spectral power density over an ultra-broad spectral range, thus opening new prospects for remote sensing applications, in particular through mid-infrared spectroscopy. Mid-infrared supercontinuum generation from 1.5 to 4.5 µm with sub-nanojoule femtosecond pump pulses is demonstrated by using a short segment of dispersion-engineered step-index tellurite fiber with very low OH content. Distinct group-velocity dispersion regimes in a simple design of step-index tellurite fiber are also reported, which allows to choose the nonlinear pulse propagation regime according to the required tailoring of the supercontinuum source. Numerical simulations based on the generalized nonlinear Schrödinger equation are used to determine optimized fiber parameters before experimental demonstrations. We also analyse the coherence properties of the resulting supercontinuum sources. [ABSTRACT FROM AUTHOR]

Abstract: We provide an overview of our recent work on the shaping and stability of optical continua in the long pulse regime. Fibers with normal group-velocity dispersion at all-wavelengths are shown to allow for highly coherent continua that can be nonlinearly shaped using appropriate initial conditions. In contrast, supercontinua generated in the anomalous dispersion regime are shown to exhibit large fluctuations in the temporal and spectral domains that can be controlled using a carefully chosen seed. A particular example of this is the first experimental observation of the Peregrine soliton which constitutes a prototype of optical rogue-waves. [Copyright &y& Elsevier]

Abstract: Considering a simple one-dimensional nonlinear Schrödinger optical model, we study the existence of rogue wave events in the highly incoherent state of the system and compare them with the recently identified hierarchy of rational soliton solutions. We show that rogue waves can emerge in the genuine turbulent regime and that their coherent deterministic description provided by the rational soliton solutions is compatible with an accurate statistical description of the random wave provided by the wave turbulence theory. Furthermore, the simulations reveal that even in the weakly nonlinear regime, the nonlinearity can play a key role in the emergence of an individual rogue wave event in a turbulent environment. [Copyright &y& Elsevier]

Abstract: We provide some general physical insights into the emergence of rogue wave events from optical turbulence by analyzing the long term evolution of the field. Depending on the amount of incoherence in the system (i.e., Hamiltonian), we identify three turbulent regimes that lead to the emergence of specific rogue wave events: (i) persistent and coherent rogue quasi-solitons, (ii) intermittent-like rogue quasi-solitons that appear and disappear erratically, and (iii) sporadic rogue waves events that emerge from turbulent fluctuations as bursts of light or intense flashes. [ABSTRACT FROM AUTHOR]

We demonstrate 1.7–18 µm mid-infrared coherent supercontinuum generation by means of the full transmission window of a unique dispersion-engineered step-index Ge-Se-Te fiber. Our study thus opens the entire molecular fingerprint region to future chalcogenide fiber platforms. [ABSTRACT FROM AUTHOR]

We report on the experimental demonstration of temporal manipulations of dissipative polarization domain wall solitons in a Kerr nonlinear resonator operated in a period-doubled configuration. Our experiments are performed in a coherently driven normally dispersive fiber ring cavity, in which polarization domains emerge in virtue of a spontaneous symmetry breaking phenomenon. The addition of a lumped birefringent defect into the cavity forces their polarization components to swap on a two-round-trip cycle, thus protecting them from the deleterious impact of the system's asymmetries. We exploit these symbiotic dynamics in proof-of-concept buffering experiments, in which these dissipative structures are addressed individually and temporally manipulated through phase-encoded perturbations imprinted onto the driving beam. Our results provide new insights into the practical exploitation of spontaneous symmetry breaking mechanisms and the use of two-component dissipative structures for all-optical data storage applications. • Exploitation of the spontaneous polarization symmetry breaking phenomenon in a normally dispersive fiber Kerr resonator. • Generation of highly robust polarization domain wall solitons operated in a period-doubled configuration (P2-PDWs). • Temporal manipulations of these dissipative polarization domain walls in a proof-of concept buffering experiment. [ABSTRACT FROM AUTHOR]

Highlights: [•] Fabrication of low-OH content and low-loss tellurite optical fibers. [•] Incorporation of fluoride ions makes tellurite fibers transparent up to 4μm. [•] 2000nm bandwidth supercontinuum in suspended core microstructured tellurite fiber. [Copyright &y& Elsevier]