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31.
We consider the Skyrme model using the explicit parameterization of the rotation group
through elements of its algebra. Topologically nontrivial solutions already arise in the one-dimensional case because the fundamental group of
is
. We explicitly find and analyze one-dimensional static solutions. Among them, there are topologically nontrivial solutions with finite energy. We propose a new class of projective models whose target spaces are arbitrary real projective spaces
. 相似文献
32.
33.
Anjan Biswas Swapan Konar Essaid Zerrad 《International Journal of Theoretical Physics》2007,46(1):157-169
The intra-channel collision of optical solitons, with dual-power law nonlinearity, is studied in this paper by the aid of
quasi-particle theory. The perturbation terms that are considered in this paper are the nonlinear gain and saturable amplifiers
along with filters. The suppression of soliton-soliton interaction, in presence of these perturbation terms, is acheived.
The numerical simulations support the quasi-particle theory.
OCIS codes: 060.2310; 060.4510; 060.5530; 190.3270; 190.4370. 相似文献
34.
The nonlinear Schrödinger equation which governs the dynamics of two-dimensional spatial solitons in Kerr media with periodically varying diffraction and nonlinearity has been analyzed in this paper using variational approach and numerical studies. Analytical expressions for soliton parameters have been derived using variational analysis. Variational equations and partial differential equation have been simulated numerically. Analytical and numerical studies have shown that nonlinearity management and diffraction management stabilize the pulse against decay or collapse providing undisturbed propagation even for larger energies of the incident beam. 相似文献
35.
I. Goidenko I. Tupitsyn G. Plunien 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,45(1):171-177
In this paper, we present a family of coupled higher-order
nonlinear Schr?dinger equation describing the optical soliton pulse
propagating in inhomogeneous optical fiber media. The exact N-soliton
solution and its characteristics of stabilities and novel elastic collision
properties are studied in detail. As an example, we give the relative
numerical evolutions by a soliton control system to discuss the pulses
propagation characteristics. 相似文献
36.
Single or/and multipeak solitons in plasma under relativistic electromagnetic field are reviewed. The incident electromagnetic
field is allowed to have a zero or/and nonzero initial constant amplitude. Some interesting numerical results are obtained
that include a high-number multipeak laser pulse and single or/and low-number multipeak plasma wake structures. It is also
shown that there exists a combination of soliton and oscillation waves for plasma wake field. Also, the electron density exhibits
multi-caviton structure or the combination of caviton and oscillation. A complete eigenvalue spectrum of parameters is given
wherein some higher peak numbers of multipeak electromagnetic solitons in the plasma are included. Moreover, some interesting
scaling laws are presented for field energy via numerical approaches. Some implications of results are discussed.
相似文献
37.
We find the existence conditions for stationary dipole and tripole surface solitons formed at the interface of a nonlocal nonlinear medium and a lattice with linearly modulated frequency. We investigate how the degree of nonlocality, the depth, and the modulation frequency of the optical lattice field affect on the existence of the surface solitons and their dynamics. The relationship between the power and the model parameters is identified. The stability of the surface dipole and tripole solitons is numerically investigated. 相似文献
38.
The study of the analytic structure of nonlinear ordinary and partial differential equations is shown to provide a unified
approach to determining their properties and finding their solutions.
A course of lectures delivered at the School on Chaos and Nonlinear Dynamics held at the Indian Institute of Science, Bangalore,
India (June 24th–July 18th 1987) 相似文献
39.
40.
Coupled backward and forward wave amplitudes of an electromagnetic field propagating in a periodic and nonlinear medium at Bragg resonance are governed by the nonlinear coupled mode equations (NLCME). This system of PDEs, similar in structure to the Dirac equations, has gap soliton solutions that travel at any speed between 0 and the speed of light. A recently considered strategy for spatial trapping or capture of gap optical soliton light pulses is based on the appropriate design of localized defects in the periodic structure. Localized defects in the periodic structure give rise to defect modes, which persist as nonlinear defect modes as the amplitude is increased. Soliton trapping is the transfer of incoming soliton energy to nonlinear defect modes. To serve as targets for such energy transfer, nonlinear defect modes must be stable. We therefore investigate the stability of nonlinear defect modes. Resonance among discrete localized modes and radiation modes plays a role in the mechanism for stability and instability, in a manner analogous to the nonlinear Schrödinger/Gross-Pitaevskii (NLS/GP) equation. However, the nature of instabilities and how energy is exchanged among modes is considerably more complicated than for NLS/GP due, in part, to a continuous spectrum of radiation modes which is unbounded above and below. In this paper we (a) establish the instability of branches of nonlinear defect states which, for vanishing amplitude, have a linearization with eigenvalues embedded within the continuous spectrum, (b) numerically compute, using Evans function, the linearized spectrum of nonlinear defect states of an interesting multiparameter family of defects, and (c) perform direct time-dependent numerical simulations in which we observe the exchange of energy among discrete and continuum modes. 相似文献