Now showing items 1-11 of 11

  • All-optical soliton control in photonic lattices 

    Xu, Zhiyong (Universitat Politècnica de Catalunya, 2007-11-27)
    Doctoral thesis
    Open Access
    Los solitones ópticos son paquetes de luz (haces y/o pulsos) que no se dispersan gracias al balance entre difracción/dispersión y no linealidad. Al propagarse e interactuar los unos con los otros muestran propiedades que ...
  • Gap solitons supported by optical lattices in photorefractive crystals with asymmetric nonlocality 

    Xu, Zhiyong; Kartashov, Yaroslav V.; Torner Sabata, Lluís (2006-06)
    Article
    Restricted access - publisher's policy
    We address the impact of the asymmetric nonlocal diffusion nonlinearity of gap solitons supported by photorefractive crystals with an imprinted optical lattice. We reveal how the asymmetric nonlocal response alters the ...
  • Multicolor vortex solitons in two-dimensional photonic lattices 

    Xu, Zhiyong; Kartashov, Yaroslav V.; Crasovan, L C; Mihalache, Dumitru; Torner Sabata, Lluís (2005-01)
    Article
    Restricted access - publisher's policy
    We report on the existence and stability of multicolor lattice vortex solitons constituted by coupled fundamental frequency and second-harmonic waves in optical lattices in quadratic nonlinear media. It is shown that the ...
  • Nonlinear photonic crystals near the supercollimation point 

    Xu, Zhiyong; Maes, B; Jiang, X; Joannopoulos, J D; Torner Sabata, Lluís; Soljacic, M (2008-08)
    Article
    Restricted access - publisher's policy
    We uncover a strong coupling between nonlinearity and diffraction in a photonic crystal at the supercollimation point. We show that this is modeled by a nonlinear diffraction term in a nonlinear-Schrödinger-type equation ...
  • Reconfigurable directional couplers and junctions optically induced by nondiffracting Bessel beams 

    Xu, Zhiyong; Kartashov, Yaroslav V.; Torner Sabata, Lluís; Vysloukh, Victor A. (2005-05)
    Article
    Restricted access - publisher's policy
    We put forward the concept of reconfigurable structures optically induced by mutually incoherent nondiffracting Bessel beams in Kerr-type nonlinear media. We address collinear couplers and X junctions and show how one can ...
  • Reconfigurable soliton networks optically-induced by arrays of nondiffracting Bessel beams 

    Xu, Zhiyong; Kartashov, Yaroslav V.; Torner Sabata, Lluís (2005-03)
    Article
    Restricted access - publisher's policy
    We address the propagation of solitons in reconfigurable two-dimensional networks induced optically by arrays of nondiffracting Bessel beams in Kerr-type nonlinear media. We show that broad soliton beams can move across ...
  • Soliton mobility in nonlocal optical lattices 

    Xu, Zhiyong; Kartashiv, Y V; Torner Sabata, Lluís (2005-09)
    Article
    Restricted access - publisher's policy
    We address the impact of nonlocality in the physical features exhibited by solitons supported by Kerr-type nonlinear media with an imprinted optical lattice. We discover that the nonlocality of the nonlinear response can ...
  • Spatiotemporal discrete multicolor solitons 

    Xu, Zhiyong; Kartashov, Yaroslav V.; Crasovan, L C; Mihalache, Dumitru; Torner Sabata, Lluís (2004-12)
    Article
    Restricted access - publisher's policy
    We have found various families of two-dimensional spatiotemporal solitons in quadratically nonlinear waveguide arrays. The families of unstaggered odd, even, and twisted stationary solutions are thoroughly characterized ...
  • Stabilization of vector soliton complexes in nonlocal nonlinear media 

    Xu, Zhiyong; Kartashov, Yaroslav V.; Torner Sabata, Lluís (2006-05)
    Article
    Restricted access - publisher's policy
    We introduce vector soliton complexes in nonlocal Kerr-type nonlinear media. We discover that under proper conditions the combination of nonlocality and vectorial coupling has a remarkable stabilizing action on multihumped ...
  • Two-dimensional multi-pole solitons in nonlocal nonlinear media 

    Rotschild, C; Segev, M; Xu, Zhiyong; Kartashov, Yaroslav V.; Torner Sabata, Lluís; Cohen, O (2006-10)
    Article
    Restricted access - publisher's policy
    We present the experimental observation of scalar multipole solitons in highly nonlocal nonlinear media, including dipole, tripole, quadrupole, and necklace-type solitons, organized as arrays of out-of-phase bright spots. ...
  • Upper threshold for stability of multipole-mode solitons in nonlocal nonlinear media 

    Xu, Zhiyong; Kartashov, Yaroslav V.; Torner Sabata, Lluís (2005-12)
    Article
    Restricted access - publisher's policy
    We address the stability of multipole-mode solitons in nonlocal Kerr-type nonlinear media. Such solitons comprise several out-of-phase peaks packed together by the forces acting between them. We discover that dipole-, ...