Nonlinear polaritons in Bose-Einstein condensates in optical lattices

We study the interaction of a Bose-Einstein condensate in an optical lattice with additional electromagnetic fields under Raman resonance condition. System of evolution equations describing ultra-short optical pulse propagation and photo-induced transport of cold atoms in optical lattice is derived. The steady state solution of these equations was found. There are new kinds of polaritonic solitary waves propagating.Comment: pdf-file, Reported on "IX International Readings on Quantum Optics", 12-17 October, St-Peterburg, Russi

Electromagnetic wave propagation in a nonlinear hyperbolic medium

The propagation of a quasi-harmonic electromagnetic wave in a bulk hyperbolic dielectric metamaterial is considered. If the group velocities dispersion is not taken into account, then wave propagation can be described either by the hyperbolic nonlinear Schrodinger equation or by the hyperbolic Manakov equations. It is shown that the region in the space of wave vectors in which the modulation instability of a spatially homogeneous wave is possible is not limited, in contrast to the case of ordinary media.Comment: 13 pages, no figures, it was submitted to Quantum Electronic

Solitary electromagnetic waves propagation in the asymmetric oppositely-directed coupler

We consider the electromagnetic waves propagating in the system of coupled waveguides. One of the system components is a standard waveguide fabricated from nonlinear medium having positive refraction and another component is a waveguide produced from an artificial material having negative refraction. The metamaterial constituting the second waveguide has linear characteristics and a wave propagating in the waveguide of this type propagates in the direction opposite to direction of energy flux. It is found that the coupled nonlinear solitary waves propagating both in the same direction are exist in this oppositely-directed coupler due to linear coupling between nonlinear positive refractive waveguide and linear negative refractive waveguide. The corresponding analytical solution is found and it is used for numerical simulation to illustrate that the results of the solitary wave collisions are sensible to the relative velocity of the colliding solitary waves.Comment: 9 pages,5 figure

Field Distribution into Binary Linear Waveguide Array

The binary (two-component) linear waveguide array that is formed either from identical waveguides but with alternating distances between adjacent waveguides, or waveguides with a positive refractive index, but having distinctions in the refractive index or the waveguide thickness. The exact solution of the coupled wave equations describing the field distribution over waveguides is found. These solutions describe the discrete diffraction in the model under consideration. Keywords: coupled waveguides, binary array, discrete diffraction, generation function method