Parametric self-trapping in the presence of randomized quasi phase matching

Abstract

We report on experimental evidence of parametric spatial solitons in a quadratic crystal with randomized periodic ferroelectric poling. Two-color self-focusing via quadratic cascading overcomes the diffractive nature of both fundamental and frequency-doubled beams.

Two-level laser by the interaction of self-induced transparency pulses and surface Anderson localizations of light

“…(38)] has to be small with respect to the leading term, the SIT system [Eqs. (26), (27), and (28)]. When the strength of disorder increases, the perturbation S p becomes of the same order of the SIT soliton equations and the SVEA approximation is no longer valid.…”

“…By increasing the scattering strength, we find that the soliton is first slowed down and finally trapped in a specific spatial region of the medium in which the coupling with the spatially localized states is maximum [25]. Once the soliton is localized in the cavity, laser emission by the two-level atoms is achieved [26][27][28]. In this paper, we use analytical and numerical approaches, the first making use of a perturbative analysis of the SIT equations and the second with the support of massively parallel numerical calculations of the full MB equations.…”

Deflection of nematicons through interaction with dielectric particles

“…Bright optical spatial solitons have been investigated in a large variety of dielectric media with diverse nonlinearities [1,2], including Kerr and Kerr-like media from gas to semiconductors to glasses to organics [3][4][5][6][7][8], thermo-optic and photorefractive materials [9,10], parametric crystals [11][12][13], lattices [14], random media [15,16], etc. In liquid crystals, particularly in the nematic phase, they have attracted a great deal of interest in both thermal and reorientational regimes [17][18][19][20], including more recently the synergetic combination of electronic (local, instantaneous) and reorientational (nonlocal, noninstantaneos) nonlinearities [21,22].…”

Random quasi-phase matching in congruent lithium tantalate waveguides by proton exchange

“…In particular, rQPM in conjunction with domain pitch in the sub-micron range allows enhancing the broadband character of the parametric response with phase-velocity matching enlarged in wavevector angular spread and size [5][6][7][8][9]. rQPM with quadratic cascading [13] in planar LT waveguides and pulsed excitation was shown to support two-colour soliton-like propagation as well [14].In this Letter we discuss a broadband frequency doubler in a rQPM waveguide realised in LT by PE. We report on its nonlinear characterisation with continous-wave (CW) excitation, on the observation of rQPM in a planar waveguide, and on a comparison between bulk and guidedwave results on the near-field SH signal and its spectral features.…”

“…In particular, rQPM in conjunction with domain pitch in the sub-micron range allows enhancing the broadband character of the parametric response with phase-velocity matching enlarged in wavevector angular spread and size [5][6][7][8][9]. rQPM with quadratic cascading [13] in planar LT waveguides and pulsed excitation was shown to support two-colour soliton-like propagation as well [14].…”