Autore: laboratorio

We present a direct experimental confirmation of the maximization of entropy which accompanies the thermalizationof a highly multimode light beam, upon its nonlinear propagation in standard graded-index (GRIN) optical fibers. The spatial beam self-cleaning effect consists of the nonlinear transformation Read More …

This research investigates the visible upconversion luminescence which is induced bymultiphoton absorption of soft glass fiber defects. The study of this phenomenon has thus far beenrestricted to standard silica fibers. We observed the emission of green and cyan light as Read More …

In this work, we study the bifurcation structures and the stability of multidimensional localized states withincoherently driven Kerr optical cavities with parabolic potentials in 1D, 2D, and 3D systems. Based on symmetricconsiderations, we transform higher-dimensional models into a single 1D Read More …

Recent studies have shown that light propagating in a nonlinear, highly multimode system canthermalize in a manner totally analogous to that encountered in traditional statistical mechanics. At thermalequilibrium, the system’s entropy is at a maximum, in full accord with the Read More …

We analyze the formation of three-dimensional spatiotemporal solitons in waveguides with a parabolic refractive index profile and pure quartic chromatic dispersion. We show, by applying both variational approaches and full three-dimensional numerical simulations, that fourth-order dispersion has a positive impact Read More …

We present a general approach to excite robust dissipative three-dimensional and high-order solitons and breathers in passively driven nonlinear cavities. Our findings are illustrated in the paradigmatic example provided by an optical Kerr cavity with diffraction and anomalous dispersion, with Read More …

The high loss due to the presence of strong phonon resonances makes silica fibers unfit for applications in the mid-infrared spectral range. This has led to the development of specialty optical fibers, based on novel materials and manufacturing techniques. In Read More …

Optical pulses traveling through multimode optical fibers encounter the influence of both linear disturbances and nonlinearity, resulting in a complex and chaotic redistribution of power among different modes. In our research, we explore the phenomenon where multimode fibers reach stable Read More …

Spatial beam self-cleaning, a manifestation of the Kerr effect in graded-index multimode fibers, involves a nonlinear transfer of power among modes, which leads to robust bell-shaped output beams. The resulting mode power distribution can be described by statistical mechanics arguments. Read More …

We introduce and experimentally demonstrate the concept of all-optical beam switching in graded-index multimode optical fibers. Nonlinear coupling between orthogonally polarized seed and signal beams permits to control the spatial beam quality at the fiber output. Remarkably, we show that Read More …