Self-organization of spatial solitons

Abstract

Abstract:We present experimental results on the transverse modulation instability of an elliptical beam propagating in a bulk nonlinear Kerr medium, and the formation and self-organization of spatial solitons. We have observed the emergence of order, self organization and a transition to an unstable state. Order emerges through the formation of spatial solitons in a periodic array. If the initial period of the array is unstable the solitons will tend to self-organize into a larger (more stable) period. Finally the system transitions to a disordered state where most of the solitons disappear and the beam profile becomes unstable to small changes in the input energy.

Femtosecond filamentation in transparent media

“…Anticipating on the next section, the examples here concern filamentation in condensed media. Centurion et al (2005a) have shown the emergence of a self-organized line of filaments in CS 2 that is finally destroyed by the fusion and repulsion of in-phase or out of phase neighboring filaments, the phase difference being accumulated along the propagation path with linear and nonlinear contributions. have used a grid so as to impose a diffraction pattern overcoming the inherent beam irregularities which naturally give rise to random small-scale multiple filamentation.…”

Holographic capture of femtosecond pulse propagation

“…Femtosecond time-resolved optical polarigraphy can be used to observe nonlinear index changes induced through the Kerr effect. 11,12 This technique captures the transient birefringence induced in the medium, but does not capture isotropic index changes. We have previously demonstrated a holographic technique 13 that captures laser-induced plasma formation with 150 fs time resolution and recovers amplitude and phase information with a spatial resolution of 4 m. Laser pulses with duration of 150 fs probe the changes in the material properties induced by a high energy pump pulse.…”

Formation of periodic multifilamentary structures by use of highly elliptic light beams

“…Beam breakup starts evolving along the major axis and ends up with stable and entirely predictable MF patterns. To this regard, reproducible MF patterns by slightly elliptical beams had been observed in various nonlinear media: water [9], air [10], BK7 glass [11], fused silica [12], and carbon disulfide [13], all revealing the universality of the deterministic breakup process.…”