Biomedical subjects

S Bar-Ad

Publications and source records attributed to S Bar-Ad.

10 recordsLinked to original sources

PubMed2006

Interaction-induced localization of anomalously diffracting nonlinear waves.

We study experimentally the interactions between normal solitons and tilted beams in glass waveguide arrays. We find that as a tilted beam, traversing away from a normally propagating soliton, coincides with the self-defocusing regime of the array, it can be refocused and routed back into any of the intermediate sites due to the interaction, as a function of the initial phase difference. Numerically, distinct parameter regimes exhibiting this behavior of the interaction are identified.

Journal Article↗

PubMed2005

Near-field imaging of nonlinear pulse propagation in planar silica waveguides.

A simplified near-field scanning optical microscope is employed to image the propagation of short laser pulses in planar silica waveguides, in the anomalous dispersion regime, under varying conditions of input beam power and width. Our results show a complex evolution of the transverse intensity profiles of the beam when there is a pronounced difference between the input diffraction and dispersion lengths. Numerical simulations confirm that these complex spatial dynamics are intimately related to the temporal and spectral evolution of the pulse.

Journal Article↗

PubMed2003

Strong spatiotemporal localization in a silica nonlinear waveguide array.

We investigate the propagation of short, intense laser pulses in arrays of coupled silica waveguides, in the anomalous dispersion regime. The nonlinearity induces trapping of the pulse in a single waveguide, over a wide range of input parameters. A sharp transition is observed for single waveguide excitation, from strong diffraction at low powers to strong localization at high powers.

Journal Article↗

PubMed2001

Kerr spatiotemporal self-focusing in a planar glass waveguide.

We observed simultaneous focusing in both space and time for light pulses propagating in a planar waveguide. In particular, 60 fs pulses with a width of 170 microm were injected into a planar glass waveguide in the anomalous dispersion regime. Output pulses as short as 30 fs and as narrow as 20 microm were measured. The results suggest that multiphoton absorption and intrapulse stimulated Raman scattering arrest the spatiotemporal contraction. The results were compared to the pulse evolution in zero and normal dispersion regimes and were shown to be significantly different. All of the experimental results were reproduced by a numerical model.

Journal Article↗

PubMed1996