MIDIT OFD CATS Modelling, Nonlinear Dynamics Optics and Fluid Dynamics Chaos and Turbulence Studies and Irreversible Thermodynamics Risø National Laboratory Niels Bohr Institute and Technical University of Denmark Building 128 Department of Chemistry Building 321 P.O. Box 49 University of Copenhagen DK-2800 Lyngby DK-4000 Roskilde DK-2100 Copenhagen Ø Denmark Denmark Denmark
by Dr. Sergei Mingaleev
Bogolyubov Institute of Theoretical Physics,
Thursday October 19, 2000, 15 h
at MIDIT, IMM, Bldg. 305, Room 027, DTU,
Abstract: Employing the technique based on Green's function, we develop a consistent theory of nonlinearity-induced self-trapping effects in 2D photonic bandgap (PBG) crystals with a Kerr nonlinearity. Specifically, we consider nonlinear localised modes in PBG crystals of reduced symmetry and in PBG crystal waveguides. We show that such modes can be described by the nonlinear Schrödinger equation with long-range dispersion in both, linear and nonlinear, terms. We demonstrate that the long-range character of the dispersion is responsible for new qualitative effects such as stabilisation of low-amplitude 2D nonlinear localised modes in reduced symmetry PBG crystals or multistability of nonlinear localised modes in the waveguides.