Spatiotemporal light localization in infiltrated waveguide arrays

We study light propagation in hexagonal waveguide arrays and show that simultaneous spatiotemporal localisation is possible by combination of engineered anomalous dispersion through selective excitation of Bloch-modes and spatial confinement in a nonlinear defect mode

Planar n-fold beam splitter based on adiabatic light transfer

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Simultaneous fs pulse spectral broadening and third harmonic generation in highly nonlinear fibre : experiments and simulations

International audienceExperiments and numerical simulations are used to study non-phasematched single-mode third harmonic generation occuring simultaneously with fs pulse spectral broadening in highly nonlinear fibre. Pump pulses around 100 fs at 1560 nm injected into sub-5 cm lengths of commercially-available highly nonlinear fibre are observed to undergo spectral broadening spanning over 700 nm at the - 30 dB level, and to simultaneously generate third harmonic radiation around 520 nm. Simulations based on a generalized nonlinear envelope equation are shown to well reproduce the spectral structure of the broadened pump pulses and the generated third harmonic signal

Optimized one-step compression of femtosecond fibre laser pulses to 30 fs in dispersion-flattened highly nonlinear fibre

International audienceIn this paper, however, we show that it is possible to obtain high quality nonlinear compressed pulses using only one segment of readily-available highly nonlinear fiber (HNLF). By directly splicing a very short (7 cm) length of HNLF to the output single mode fiber pigtail of a commercial femtosecond fiber laser, frequency resolved optical gating (FROG) confirms that nonlinear compression results in the generation of 28 fs pulses. This represents an extremely simple modification allowing an essentially loss-free factor-of-three reduction in pulse duration relative to the primary source

Temporal dynamics of spatially localized waves in quadratic nonlinear waveguide arrays

We study experimentally and theoretically the temporal dynamics of laser pulses propagating under conditions of spatial self-focusing in quadratic nonlinear waveguide arrays made from periodically poled lithium niobate. We observed temporal pulse breakup and temporal pulse narrowing and studied the dynamics of these effects in different waveguides. We investigated the influence of the frequency dependence of the mode indices as a limiting factor for soliton formation. Our experimental results are in good agreement with the theoretical model developed from coupled-mode theory, providing a detailed understanding of pulse dynamics and beam distribution in waveguide arrays with quadratic nonlinearity

Phase transition of discrete quadratic solitons

We predict theoretically and observe experimentally an abrupt power-controlled transition from unstaggered to staggered second harmonic phase profiles of discrete solitons with linear second harmonic coupling in periodically poled waveguide arrays