We study the formation and interaction of spatial dark optical solitons in materials with a nonlocal nonlinear response. show that unlike local materials, where typically repel, nonlinearity leads to long-range attraction stable bound states solitons.

Near-threshold operation of a semiconductor laser exposed to moderate optical feedback may lead low-frequency fluctuations. In the same region, kink is observed in light-current characteristic. Here it demonstrated that these nonlinear phenomena are predicted by noise driven multimode traveling-wave model. The dynamics fluctuations explained qualitatively terms bistability through an iterative description.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML"...

A detailed numerical study of a sine-Gordon model the Josephson tunnel junction is compared with experimental measurements on junctions different $\frac{L}{{\ensuremath{\lambda}}_{J}}$ ratios. The soliton picture found to apply well both relatively long ($\frac{L}{{\ensuremath{\lambda}}_{J}}=6$) and intermediate ($\frac{L}{{\ensuremath{\lambda}}_{J}}=2$) junctions. We find good agreement for current-voltage characteristics, power output, shape height zero-field steps (ZFS). Two distinct...

We study the propagation of intense optical beams in layered Kerr media. With appropriate shapes, with a power close to self-focusing threshold are shown propagate over long distances as quasi-stationary waveguides cubic media supporting periodic nonlinear refractive index.

Acoustic waves on elastic rods with circular cross section are governed by improved Boussinesq equations when transverse motion and nonlinearity in the medium taken into account. Solitary wave solutions to these have been found. The present paper treats interaction between solitary numerically. It is demonstrated that behave almost like solitons agreement fact nearly integrable. Thus three conservation theorems can be derived from equations. A new subsonic quasibreather found case of a cubic...

A nonlinear dynamical model of molecular monolayers arranged in Scheibe aggregates is derived from a proper Hamiltonian. Thermal fluctuations the phonons are included. The resulting equation for excitons two dimensional Schr\"odinger with noise. Two limits complicated spectrum noise considered: time independent, spatially white noise, simply corresponding to disorder arrangement molecules, and pure Parameter values found by comparison experiments M\"obius Kuhn [Isr. J. Chem. 18, 375 (1979)]...

The Melnikov function for prediction of Smale horseshoe chaos is applied to the rf-driven Josephson junction. Linear and quadratic damping resistors are considered. In latter case analytic solution including dc bias used obtain an improved threshold curve onset chaos. compared new computational solutions. technique provides a good, but slightly low, estimate threshold.

A one-dimensional discrete nonlinear Schr\"odinger (NLS) model with the power dependence ${\mathrm{r}}^{\mathrm{\ensuremath{-}}\mathrm{s}}$ on distance r of dispersive interactions is proposed. The stationary states ${\mathrm{\ensuremath{\psi}}}_{\mathrm{n}}$ system are studied both analytically and numerically. Two types investigated: on-site intersite states. It shown that for s sufficiently large all features qualitatively same as in NLS a nearest-neighbor interaction. For less than some...

As a possible mechanism for energy storage and transport in proteins, Davydov has proposed soliton formation propagation. In this paper we investigate the stability of solitons at biological temperatures. From Davydov's original theory evolution equations are derived quantum mechanically without approximations, their numerical solutions different temperatures presented. Our conclusion is that stable 310 K.

Discretizing the continuous nonlinear Schrodinger equation with arbitrary power nonlinearity influences time evolution of its ground state solitary solution. In subcritical case, for grid resolutions above a certain transition value, depending on degree nonlinearity, solution will oscillate smoothly frequency and amplitude that depend both resolution nonlinearity. Thus in this region discrete system give good reproduction dynamics continuum one. However, when discretization gets too coarse...

Ring-shaped solitary wave solutions to the Sine-Gordon equation in two and three spatial dimensions are investigated by numerical computation. Each expanding exhibits a return effect. The reflection of shrinking at singularity center is particular case. Collision experiments numero for concentric ring waves show that possess quasisoliton properties. A Bäcklund transformation non-symmetric three-dimensional case given.

A nonlinear fiber with a gain that has symmetric lateral frequency bands is found to generate stable train of bright or dark pulses well-defined repetition rate. The pulse generated from noise; the are unchirped, and their amplitude rate determined by parameters system. underlying mechanism for this formation recognized as dissipative four-wave mixing in which only two frequencies nonnegligible; one near maximum transmits energy wave its third harmonic, region negative gain. An implicit...

The scattering properties of regularizing finite-range potentials constructed in the form squeezed rectangles, which approximate first and second derivatives Dirac delta function δ(x), are studied zero-range limit. Particularly, for a countable set interaction strength values, non-zero transmission through point potential δ'(x), defined as weak limit (in standard sense distributions) special dipole-like sequence is shown to exist when rectangles zero width. A tripole gives distribution...

We consider travelling periodic and quasiperiodic wave solutions of a set coupled nonlinear Schr\"odimger equations. In fibre optics these equations can be used to model single mode fibers with strong birefringence two-mode optical fibres. Recently appear as modes, which describe pulse-pulse interaction in wavelength-division-multiplexed channels fiber transmission systems. Two phase quasi-periodic for integrable Manakov system are given tems two-dimensional Kleinian functions. The reduction...

Weak modulation of a quasi-phase-matching (QPM) grating opens possibilities for engineering both the average quadratic nonlinearity and incoherent cubic induced by QPM. The relative strength effective (intrinsic plus induced) is studied LiNbO(3) . We show how can be engineered to dominate intrinsic material doing so will allow intensity at which nonlinearities balance thus compete decreased few gigawatts per square centimeter.