Negative refraction and spatial echo in optical waveguide arrays

The special symmetry properties of the discrete nonlinear Schrodinger equation allow a complete revival of the initial wavefunction. That is employed in the context of stationary propagation of light in a waveguide array. As an inverting system we propose a short array of almost isolated waveguides which cause a relative pi phase shift in the neighboring waveguides. By means of numerical simulations of the model equations we demonstrate a novel mechanism for the negative refraction of spatial solitons.Comment: 3 pages, 2 figure

Far-off-resonant wave interaction in one-dimensional photonic crystals with quadratic nonlinearity

We extend a recently developed Hamiltonian formalism for nonlinear wave interaction processes in spatially periodic dielectric structures to the far-off-resonant regime, and investigate numerically the three-wave resonance conditions in a one-dimensional optical medium with $\chi^{(2)}$ nonlinearity. In particular, we demonstrate that the cascading of nonresonant wave interaction processes generates an effective $\chi^{(3)}$ nonlinear response in these systems. We obtain the corresponding coupling coefficients through appropriate normal form transformations that formally lead to the Zakharov equation for spatially periodic optical media.Comment: 14 pages, 4 figure

Nonlinear Wave Interaction In Photonic Band Gap Materials

We present detailed analytical and numerical studies of nonlinear wave interaction processes in one-dimensional (1D) photonic band gap (PBG) materials with a Kerr nonlinearity. We demonstrate that some of these processes provide efficient mechanisms for dynamically controlling so-called gap-solitons. We derive analytical expressions that accurately determine the phase shifts experienced by nonlinear waves for a large class of non-resonant interaction processes. We also present comprehensive numerical studies of inelastic interactions, and show that rather distinct regimes of interaction exist. The predicted effects should be experimentally observable, and can be utilized for probing the existence and parameters of gap solitons. Our results are directly applicable to other nonlinear periodic structures such as Bose-Einstein condensates in optical lattices. © 2006

Justification Of The Nonlinear Schrödinger Equation In Spatially Periodic Media

The dynamics of the envelopes of spatially and temporarily oscillating wave packets advancing in spatially periodic media can approximately be described by solutions of a Nonlinear Schrödinger equation. Here we prove estimates for the error made by this formal approximation using Bloch wave analysis, normal form transformations, and Gronwall\u27s inequality. © Birkhäuser Verlag, Basel 2006

All-Optical Diode In An Asymmetrically Apodized Kerr Nonlinear Microresonator System

We show numerically that a Kerr nonlinear system composed of two channel waveguides coupled periodically by circular microresonators can be used as an all optical diode. The diode has low intensity requirements ( ∼ 50 MW/cm2) and compact dimensions (∼ 100 μm). © 2004 Elsevier B.V. All rights reserved