In this article, by using the method of finite difference time domain (FDTD) and PML boundary conditions, we have studied the photonic band gaps for TE and TM modes in square and triangular lattices consisting of air holes in dielectric medium and compared the results. In addition, the effect of nonlinearity of the photonic crystal background on the photonic band gaps and comparison with the re...

The nonlinear supratransmission is the property of a nonlinear system possessing a natural forbidden band gap to transmit energy of a signal with a frequency in the gap by means of generation of nonlinear modes (gap solitons). This process is shown to result from a generic instability of the evanescent wave profile generated in a nonlinear medium by the incident signal.

The aim of the paper is to analyze electro-thermo nonlinear vibration of a double-piezoelectric composite microplate-system (DPCMPS) based on nonlocal piezoelasticity theory. The two microplates are assumed to be connected by an enclosing elastic medium which is simulated by Pasternak foundation. Both of smart composite microplates are made of poly-vinylidene fluoride (PVDF) reinforced by zigza...

We consider a one-dimensional elastic string as a set of massless beads interacting through springs characterized by anisotropic elastic constants. The string, driven by an external force, moves in a medium with quenched disorder. We find that longitudinal fluctuations lead to nonlinear behavior in the equation of motion that is kinematically generated by the motion of the string. The strength ...

In the present work, effect of von Karman geometric nonlinearity on the vibration characteristics of a Y-shaped single walled carbon nanotube (Y-SWCNT) conveying viscose fluid is investigated based on Euler Bernoulli beam (EBB) model. The Y-SWCNT is also subjected to a longitudinal magnetic field which produces Lorentz force in transverse direction. In order to consider the small scale effects,...

A scheme for polarization control using two laser beams in a non-linear optical medium is studied both co- and counter-propagating beam geometries. In particular, we show that under certain conditions it possible to exchange their states. model accounting more realistic, 2D propagation geometry presented. The produces drastically different results (compared the 1D geometry), creating difficulti...

Many dissipative optical systems support patterns. Dissipative solitons are generally found where a pattern coexists with a stable unpatterned state. We consider such phenomena in driven optical cavities containing a nonlinear medium (cavity solitons) and rather similar phenomena (feedback solitons) where a driven nonlinear optical medium is in front of a single feedback mirror. The history, th...

the aim of the paper is to analyze electro-thermo nonlinear vibration of a double-piezoelectric composite microplate-system (dpcmps) based on nonlocal piezoelasticity theory. the two microplates are assumed to be connected by an enclosing elastic medium which is simulated by pasternak foundation. both of smart composite microplates are made of poly-vinylidene fluoride (pvdf) reinforced by zigza...

a) Develop the nonlinear acoustic theory of poroelastic media using Biot’s semilinear model and physical model of contact nonlinearity, b) Measure the nonlinear parameter of sediments in laboratory tank, c) Study the effect of sediment parameters (grain size distribution, free gas content, porosity) on nonlinear acoustic properties of the sediments, d) Evaluate the nonlinear absorption and dist...