We present a new multi-parameter family of analytical soliton solutions for nonlinear three-wave resonant interactions.
We show the amplitude, phase-front shapes and general properties of the solitons. The stability of these
novel parametric solitons is simply related to the value of their common group velocity.
We present theoretical and experimental studies of both scalar and polarization or modal pump-divided parametric
amplification in photonic crystal fibers. In the scalar case, we discuss broadband parametric amplification at telecom
wavelengths near 1550 nm. With a pump-divided scattering process, we discuss the possibility of widely tunable
frequency conversion and four-wave mixing gain at visible wavelengths. We confirmed the theory by experiments where
intense, linearly polarized pump pulses at wavelengths ranging from 532 to 625 nm led to the spontaneous generation of
modulation instability sidebands with frequency shifts ranging from 3 up to 63 THz. The observations were in good
agreement the experimental characterization and theoretical modelling ofthe linear and nonlinear properties of the PCF.
We study the effects of the induced third-order nonlinearity on backward second-harmonic generation in Penodically
Poled Lithium Niobate (PPLN). We show that self-phase and cross-phase modulation terms induced
by a proper engineering of the domain length can compete with intrinsic quadratic nonlinearity enriching the
dynamics of the system. In particular it allows for self oscillation even with vanishing second-harmonic input.