Magnetostatic spin solitons in ferromagnetic nanotubes

We study the linear and nonlinear evolution of a magnetostatic spin wave (MSW) in a charge free, isotropic ferromagnetic hollow nanotube. By analyzing the dispersion relation we observe that elliptically polarized forms of wave can propagate through the ferromagnetic nanotube. Using the multiple scale analysis we find that the dynamics of magnetization of the medium is governed by the cubic nonlinear Schrödinger equation. The stability of the continuous wave, related to the propagation of either bright or dark (MS) solitons in the nanotube, is governed by the direction of the external magnetic field relative to the magnetized nanotube

AdS-Carroll Branes

Coset methods are used to determine the action of a co-dimension one brane (domain wall) embedded in (d+1)-dimensional AdS space in the Carroll limit in which the speed of light goes to zero. The action is invariant under the non-linearly realized symmetries of the AdS-Carroll spacetime. The Nambu-Goldstone field exhibits a static spatial distribution for the brane with a time varying momentum density related to the brane's spatial shape as well as the AdS-C geometry. The AdS-C vector field dual theory is obtained.Comment: 47 page

Lorentz Transformation from Symmetry of Reference Principle

The Lorentz Transformation is traditionally derived requiring the Principle of Relativity and light-speed universality. While the latter can be relaxed, the Principle of Relativity is seen as core to the transformation. The present letter relaxes both statements to the weaker, Symmetry of Reference Principle. Thus the resulting Lorentz transformation and its consequences (time dilatation, length contraction) are, in turn, effects of how we manage space and time.Comment: 2 page

Anyons, group theory and planar physics

Relativistic and nonrelativistic anyons are described in a unified formalism by means of the coadjoint orbits of the symmetry groups in the free case as well as when there is an interaction with a constant electromagnetic field. To deal with interactions we introduce the extended Poincar\'e and Galilei Maxwell groups.Comment: 22 pages, journal reference added, bibliography update

Fifth-order nonlinear susceptibility: Effect of third-order resonances in a classical theory

We compute the fifth-order nonlinear susceptibility in the frame of a classical model based on an anharmonic oscillator, taking into account the local field corrections. A third-harmonic resonance is evidenced, which explains the strong enhancement of some measured values of the corresponding nonlinear index and its sign changes with the wavelength. The ratio between the fifth-order nonlinear index and the fifth-order nonlinear absorption is computed and is in good agreement with experimental data measured in carbon disulfide CS2

Galilean Lee Model of the Delta Function Potential

The scattering cross section associated with a two dimensional delta function has recently been the object of considerable study. It is shown here that this problem can be put into a field theoretical framework by the construction of an appropriate Galilean covariant theory. The Lee model with a standard Yukawa interaction is shown to provide such a realization. The usual results for delta function scattering are then obtained in the case that a stable particle exists in the scattering channel provided that a certain limit is taken in the relevant parameter space. In the more general case in which no such limit is taken finite corrections to the cross section are obtained which (unlike the pure delta function case) depend on the coupling constant of the model.Comment: 7 pages, latex, no figure

Determination of the third- and fifth-order optical nonlinearities: the general case

We compute the evolution of the intensity (I) and the phase (phi) of a beam propagating in a nonlinear (NL) isotropic medium exhibiting third- and fifth-order NL optical characteristics. All formulas are analytic, but the general case requires a numerical inversion by means of Newton’s method. The solutions may differ if some coefficients vanish, so they are given in all cases up to the fifth-order nonlinearities. The analytical relations allow us to fit the experimental data using the recently introduced D4sigma-Z-scan method. Carbon disulfide is tested at 532 and 1,064 nm in the picosecond regime deducing NL coefficients related to third- and fifth-order optical susceptibilities

Filamentation of light in carbon disulfide

We report experimental observation of light filamentation in carbon disulfide (CS2). Accurate measurements of the nonlinear index show an unusual saturation law of the Kerr effect, which is used to build a model of light propagation in CS2, which describes the filamentation in good agreement with experimental observations

Multiscale theory of nonlinear wavepacket propagation in a planar optical waveguide

In this paper, the multiscale expansion formalism is applied for the first time, to our knowledge, in nonlinear planar optical waveguides. This formalism permits us to describe the linear and nonlinear propagation for both transverse electric and transverse magnetic modes. The modal field distributions and the nonlinear coefficient in the nonlinear Schrödinger equation are highlighted

Polarization switching in a planar optical waveguide

The multiscale expansion formalism is applied to the study of nonlinear planar optical waveguides. It allows us to describe the linear and nonlinear propagation for both transverse electric and transverse magnetic modes, and the interaction between them. An accurate computation of the nonlinear self- and cross-phase modulation coefficients allows one to give account of the polarization switching which has been observed experimentally