Bragg grating rogue wave

We derive the rogue wave solution of the classical massive Thirring model, that describes nonlinear optical pulse propagation in Bragg gratings. Combining electromagnetically induced transparency with Bragg scattering four-wave mixing, may lead to extreme waves at extremely low powers

Bragg solitons in nonlinear PT-symmetric periodic potentials

It is shown that slow Bragg soliton solutions are possible in nonlinear complex parity-time (PT) symmetric periodic structures. Analysis indicates that the PT-symmetric component of the periodic optical refractive index can modify the grating band structure and hence the effective coupling between the forward and backward waves. Starting from a classical modified massive Thirring model, solitary wave solutions are obtained in closed form. The basic properties of these slow solitary waves and their dependence on their respective PT-symmetric gain/loss profile are then explored via numerical simulations.Comment: 6 pages, 4 figures, published in Physical Review

Efficiency of dispersive wave generation in dual concentric core microstructured fiber

We describe the generation of powerful dispersive waves that are observed when pumping a dual concentric core microstructured fiber by means of a sub-nanosecond laser emitting at the wavelength of~1064 nm. The presence of three zeros in the dispersion curve, their spectral separation from the pump wavelength, and the complex dynamics of solitons originated by the pump pulse break-up, all contribute to boost the amplitude of the dispersive wave on the long-wavelength side of the pump. The measured conversion efficiency towards the dispersive wave at 1548 nm is as high as 50%. Our experimental analysis of the output spectra is completed by the acquisition of the time delays of the different spectral components. Numerical simulations and an analytical perturbative analysis identify the central wavelength of the red-shifted pump solitons and the dispersion profile of the fiber as the key parameters for determining the efficiency of the dispersive wave generation process.Comment: 11 pages, 12 figure

Spatial beam reshaping and spectral broadening in quadratic crystals

Nonlinear optics in crystals with quadratic susceptibility has been largely explored along the last decades, with a particular emphasis on spatial solitons. When in the initial part of the propagation, the nonlinear length is much shorter than the diffraction length, rather than solitons, in these crystals it is possible to observe strong beam reshaping and spectral broadening. This mechanism of nonlinear beam evolution can be induced by combining high laser energies and large input diameters, so to reduce the contribution of diffraction in the initial steps of the propagation

Widely varying giant Goos–Hänchen shifts from airy beams at nonlinear interfaces

We present a numerical study of the giant Goos–Hänchen shifts (GHSs) obtained from an Airy beam impinging on a nonlinear interface. To avoid any angular restriction associated with the paraxial approximation, the analysis is based on the nonlinear Helmholtz equation. We report the existence of nonstandard nonlinear GHSs displaying an extreme sensitivity to the input intensity and the existence of multiple critical values. These intermittent and oscillatory regimes can be explained in terms of competition between critical coupling to a surface mode and soliton emission from the refracted beam component and how this interplay varies with localization of the initial Airy beam

Discrete localized modes in binary waveguide arrays2013 IEEE 2nd International Workshop "Nonlinear Photonics" (NLP*2013)

We report the existence of a new class of discrete localized modes in a model describing the propagation of optical waves in nonlinear binary waveguide arrays with alternate positive and negative nearest neighbor coupling. We derive a longwave continuous approximation and characterize some nonlinear continuum brightdark soliton-like solutions and compared them with the discrete modes

Dark–antidark solitons in waveguide arrays with alternating positive–negative couplings

We obtain dark and antidark soliton solutions in binary waveguide arrays with focusing and/or defocusing Kerr nonlinearity and with alternating positive and negative linear couplings between adjacent waveguides. For both stationary and moving solitons, we analyze the properties of these solutions in the presence of uniform and nonuniform nonlinearity along the array