Ara es mostren els items 1-20 de 28

    • Bose-Einstein condensates with localized spin-orbit coupling: Soliton complexes and spinor dynamics 

      Kartashov, Yaroslav; Konotop, Vladimir V; Zezyulin, Dmitry A (2014-12-15)
      Article
      Accés obert
      Spin-orbit (SO) coupling can be introduced in a Bose-Einstein condensate (BEC) as a gauge potential acting only in a localized spatial domain. The effect of such a SO “defect” can be understood by transforming the system to ...
    • Bright solitons from defocusing nonlinearities 

      Borovkova, Olga V.; Kartashov, Yaroslav; Torner Sabata, Lluís; Malomed, Boris A. (2011-09-19)
      Article
      Accés restringit per política de l'editorial
      We report that defocusing cubic media with spatially inhomogeneous nonlinearity, whose strength increases rapidly enough toward the periphery, can support stable bright localized modes. Such nonlinearity landscapes give ...
    • Dissipative defect modes in periodic structures 

      Kartashov, Yaroslav; Konotop, Vladimir V; Vysloukh, Victor A.; Torner Sabata, Lluís (2010-05-15)
      Article
      Accés restringit per política de l'editorial
      We show that periodic optical lattices imprinted in cubic nonlinear media with strong two-photon absorption and localized linear gain landscapes support stable dissipative defect modes in both focusing and defocusing media. ...
    • Frontiers in Multidimensional Self-Trapping of Nonlinear Fields and Matter 

      Kartashov, Yaroslav; Astrakharchik, Grigori; Malomed, Boris A.; Torner Sabata, Lluís (Nature, 2019-02-22)
      Article
      Accés obert
      2D and 3D solitons and related states, such as quantum droplets, can appear in optical systems, atomic Bose–Einstein condensates (BECs) and liquid crystals, among other physical settings. However, multidimensional solitary ...
    • General quasi-nonspreading linear three-dimensional wave packets 

      Borovkova, Olga V.; Kartashov, Yaroslav; Lobanov, Valery E.; Vysloukh, Victor A.; Torner Sabata, Lluís (2011-06-15)
      Article
      Accés restringit per política de l'editorial
      We introduce a general approach for generation of sets of three-dimensional quasi-nonspreading wave packets propagating in linear media, also referred to as linear light bullets. The spectrum of rigorously nonspreading ...
    • Light bullets by synthetic diffraction-dispersion matching 

      Lobanov, Valery E.; Kartashov, Yaroslav; Torner Sabata, Lluís (2010-07-03)
      Article
      Accés obert
      We put forward a new approach to generate stable, fully three-dimensional light bullets, which is based on the matching of the intrinsic material dispersion with a suitable effective diffraction. The matching is achieved ...
    • Light dynamics in glass-vanadium dioxide nanocomposite waveguides with thermal nonlinearity 

      Kartashov, Yaroslav; Vysloukh, Victor A. (2009-04)
      Article
      Accés obert
      We address the propagation of laser beams in SiO2–VO2 nanocomposite waveguides with thermo-optical nonlinearity. We show that the large modifications of the absorption coefficient as well as notable changes of the ...
    • Light localization in nonuniformly randomized lattices 

      Kartashov, Yaroslav; Konotop, Vladimir V; Vysloukh, Victor A.; Torner Sabata, Lluís (2012)
      Article
      Accés restringit per política de l'editorial
      We address Anderson localization of light in disordered optical lattices where the disorder strength varies across the transverse direction. Such variation changes the preferred domains where formation of localized eigenmodes ...
    • Method to generate complex quasinondiffracting optical lattices 

      López Aguayo, Servando; Konotop, Vladimir V; Kartashov, Yaroslav; Torner Sabata, Lluís (2010-07-02)
      Article
      Accés obert
      We put forward a powerful technique that allows generating quasi-non-diffracting light beams with a variety of complex transverse shapes and topologies. We show that, e.g., spi-raling patterns, patterns featuring curved ...
    • Negative Goos-Hanchen shift in periodic media 

      Rechtsman, Mikael C.; Kartashov, Yaroslav; Setzpfandt, Frank; Trompeter, Henrik; Torner Sabata, Lluís; Pertsch, T.; Peschel, Ulf; Szameit, A. (2011-11-15)
      Article
      Accés restringit per política de l'editorial
      We show that, under certain conditions, a negative Goos–Hänchen shift—a longitudinal displacement of a totally internally reflected wave packet—occurs in periodic media such as waveguide arrays.
    • Nonlinearity-mediated soliton ejection from trapping potentials in nonlocal media 

      Fangwei, Ye; Kartashov, Yaroslav; Hu, Bambi; Torner Sabata, Lluís (2010-08-30)
      Article
      Accés obert
      We address the properties of optical solitons in thermal nonlinear media with a local refractive index defect that is capable to trap solitons launched even close to the sample boundary despite the boundary-mediated ...
    • Observation of the gradual transition from one-dimensional to two-dimensional Anderson localization 

      Naether, U.; Kartashov, Yaroslav; Vysloukh, Victor A.; Nolte, S.; Tünnermann, A.; Torner Sabata, Lluís; Szameit, A. (2012-02-15)
      Article
      Accés restringit per política de l'editorial
      We study the gradual transition from one-dimensional to two-dimensional Anderson localization upon transformation of the di-mensionality of disordered waveguide arrays. An effective transition from one- to two-dimensional ...
    • Observation of two-dimensional superlattice solitons 

      Heinrich, Matthias; Kartashov, Yaroslav; Ramírez, L. P. R.; Szameit, Alexander; Dreisow, Felix; Keil, R; Nolte, Stefan; Tünnermann, Andreas; Vysloukh, Victor A.; Torner Sabata, Lluís (2009-12)
      Article
      Accés restringit per política de l'editorial
      We observe experimentally two-dimensional solitons in superlattices comprising alternating deep and shallow waveguides fabricated via the femtosecond-laser direct writing technique. We find that the symmetry of linear ...
    • Resonant Bloch-wave beatings 

      Kartashov, Yaroslav; Vysloukh, Victor A.; Torner Sabata, Lluís (2014-07-01)
      Article
      Accés restringit per política de l'editorial
      We introduce Bloch-wave beatings in arrays of multimode periodically bent waveguides with a transverse refractive index gradient. The new phenomenon manifests itself in the periodic drastic increase of the amplitude of the ...
    • Resonant mode conversion in the waveguides with unbroken and broken PT symmetry 

      Vysloukh, Victor A.; Kartashov, Yaroslav (2014-10-15)
      Article
      Accés obert
      We study resonant mode conversion in parity time (PT)-symmetric multimode waveguides, where symmetry breaking manifests itself in the sequential destabilization (i.e., the appearance of complex eigenvalues) of the pairs ...
    • Rotating vortex solitons supported by localized gain 

      Borovkova, Olga V.; Lobanov, Valery E.; Kartashov, Yaroslav; Torner Sabata, Lluís (2011-05-15)
      Article
      Accés restringit per política de l'editorial
      We show that ringlike localized gain landscapes imprinted in focusing cubic (Kerr) nonlinear media with strong two-photon absorption support new types of stable higher-order vortex solitons containing multiple phase ...
    • Self-trapping and splitting of bright vector solitons under inhomogeneous defocusing nonlinearities 

      Kartashov, Yaroslav; Vysloukh, Victor A.; Torner Sabata, Lluís; Malomed, Boris A. (2011-12-01)
      Article
      Accés restringit per política de l'editorial
      We show that bimodal systems with a spatially nonuniform defocusing cubic nonlinearity, whose strength grows toward the periphery, can support stable two-component solitons. For a sufficiently strong cross-phase-modulation ...
    • Soliton gyroscopes in media with spatially growing repulsive nonlinearity 

      Driben, Rodislav; Kartashov, Yaroslav; Malomed, Boris A.; Meier, Torsten; Torner Sabata, Lluís (2014-01-15)
      Article
      Accés obert
      We find that the recently introduced model of self-trapping supported by a spatially growing strength of a repulsive nonlinearity gives rise to robust vortex-soliton tori, i.e., three-dimensional vortex solitons, with ...
    • Solitons in geometric potentials 

      Kartashov, Yaroslav; Szameit, A.; Keil, R.; Vysloukh, Victor A.; Torner Sabata, Lluís (2011-07-01)
      Article
      Accés restringit per política de l'editorial
      We show that the geometrically induced potential existing in undulated slab waveguides dramatically affects the properties of solitons. In particular, whereas solitons residing in the potential maxima do not feature power ...
    • Solitons supported by spatially inhomogeneous nonlinear losses 

      Borovkova, Olga V.; Kartashov, Yaroslav; Vysloukh, Victor A.; Lobanov, Valery E.; Malomed, Boris A.; Torner Sabata, Lluís (2012)
      Article
      Accés restringit per política de l'editorial
      We uncover that, in contrast to the common belief, stable dissipative solitons exist in media with uniform gain in the presence of nonuniform cubic losses, whose local strength grows with coordinate η (in one dimension) ...