Ion acoustic solitons in a streaming relativistic plasma with negative ions

We analyze the effect of a nonzero streaming velocity of both positive and negative ions on the formation of solitary waves in a relativistic plasma. The thermodynamic situation is considered to be isothermal. For various values ofu _0/C andn _o/nowe obtain the variations of the amplitude and the width of the solitary wave.     

Dynamics of Langmuir turbulence. Formation and interaction of solitons

We present a computer study of the formation and interaction of Langmuir solitons allowing for the generation of ion-sound waves.     

The kinetic theory of magnetic-field generation in a Langmuir plasma

We develop a two-timescale kinetic theory for the nonlinear generation process for a slow-timescale magnetic field in a hot collisionless Langmuir plasma. We show that the basic damping of this magnetic field is due to the collisionless skin effect.     

孤子和辐射场的非线性相互作用

利用穿衣服的方法推导出了在纯辐射场情况下Jost函数对的显式,由此得到了孤子与辐射场相互作用的解析表达式,发现脉冲在传输过程中,由于受到辐射场的作用,其振幅的演化在传播方向上是按照幂指数的负的平方根的规律衰减,并且将最终演化成一个类孤子的形式,且阐明了因子γ对光脉冲输出的光谱特性将会产生重要影响;并对辐射场的存在对类孤子演化的动力学行为作了分析. 关键词： 穿衣服方法 类孤子 孤子 辐射场     

Delayed-action interaction and spin-orbit coupling between solitons

We report on new fundamental phenomena in soliton interactions: delayed-action interaction and "spin"-orbit coupling upon collision between two-dimensional composite solitons carrying topological charges.     

Large amplitude electromagnetic solitons in intense laser plasma interaction

This paper shows that the standing, backward- and forward-accelerated large amplitude relativistic electromagnetic solitons induced by intense laser pulse in long underdense collisionless homogeneous plasmas can be observed by particle simulations. In addition to the inhomogeneity of the plasma density, the acceleration of the solitons also depends upon not only the laser amplitude but also the plasma length. The electromagnetic frequency of the solitons is between about half and one of the unperturbed electron plasma frequency. The electrostatic field inside the soliton has a one-cycle structure in space, while the transverse electric and magnetic fields have half-cycle and one-cycle structure respectively. Analytical estimates for the existence of the solitons and their electromagnetic frequencies qualitatively coincide with our simulation results.     

Radiation effects in the interaction between solitons and inhomogeneities

Physicotechnical Institute of Low Temperatures, Academy of Sciences of the Ukrainian SSR. Translated from Izvestiya Vysshikh Uchebnykh. Zavedenii, Radiofizika, Vol. 31, No. 11, pp. 1345–1354, November, 1988.     

Resonant interaction of the Langmuir wave with quasi-stationary plasma electrons

Evolution of the Langmuir wave in quasi-stationary plasma is considered. A consistent solution to the closed system of the Vlasov–Poisson equations is obtained in the adiabatic approximation. Dispersion of the wave evolving in the electron distribution tail with variable electron concentration or plasma temperature is described. It is established that the plasma oscillation energy increases with decreasing electron concentration or increasing temperature. After plasma regains its initial state, the wave parameters also restore their initial values. That is, the wave evolution in the quasi-stationary plasma is a completely reversible process.     

高强度激光与等离子体相互作用中的受激Raman级联散射、光子凝聚以及大振幅电磁孤立子的产生与加速

应用一维相对论电磁粒子模拟程序，详细研究了线性极化强激光入射到无碰撞稀疏密度长等离子体中引起的受激Raman散射、Raman级联散射、级联散射到光子凝聚、以及大振幅电磁孤立子的产生与加速. 通过研究发现：在适当的激光振幅和等离子体状态下，强的光子凝聚现象会导致大振幅电磁孤立子的产生，电磁孤立子可以以静止、向后以及向前加速的形式存在；在密度均匀的等离子体中，电磁孤立子的加速不仅依赖于激光振幅而且依赖于等离子体的长度；电磁孤立子的电磁频率大约为未扰动电子等离子体振荡频率的二分之一左右，孤立子内电磁场的电场具有半周期结构，相应电磁场的磁场以及静电场则具有一个完整的周期结构. 关键词： 粒子模拟 受激Raman散射 Raman级联散射 光子凝聚 电磁孤立子     

Nonlinear Langmuir waves in a relativisitc plasma

Langmuir waves in a relativistic plasma are considered using kinetic equations without consideration of captured particles. The frequency shift found for such waves contains contributions from four-wave interaction, and a contribution produced by the relativistic dependence of electron momentum on velocity.     

Incoherent interaction between one- and two-dimensional solitons in noncentrosymmetric photorefractive media

The incoherent interaction between solitons with different transverse dimensions in a noncentrosymmetric photorefractive crystal is studied both in theory and in experiment. An anomalous incoherent interaction between one- and two-dimensional solitons, whose attractive and repulsive effects depend on the soliton separation, is numerically demonstrated by employing an anisotropic model. By launching a one-dimensional green beam and a two-dimensional red beam into a biased SBN:60 crystal, the hybrid-dimensional soliton interaction is performed. The experimental results are in good agreement with the numerical ones.     

Diagnostics of Langmuir oscillations in a superdense plasma

The level and the angular distribution of Langmuir oscillations in a dense plasma produced on the Phoenix plasma radiation source (PRS) were measured. Line profiles of several lines in the Lyman series of Al XIII were measured using crystal spectrometers. A spectral line shape model was used, which attempted to take into account all significant broadening mechanisms. The parameters of the plasma and the Langmuir oscillations were found by generating profiles using the model and comparing these profiles to the experimental spectra. The strength of the Langmuir oscillations was found to be E₀≈1-9 GV/cm, indicative of a strong Langmuir turbulence. The polarization analysis of the profiles of the Al XIII Lyman γ line has shown that the Langmuir oscillations develop anisotropically, primarily in the direction of the plasma current     

Role of adjacent-pulse overlap in the interaction between dispersion-managed solitons

Periodic breathing of pulse width owing to strong dispersion management leads to significant overlap between adjacent pulses in long-distance fiber-optic transmissions. A striking result is that beyond a critical degree of overlap the interaction forces are no longer increased and are even reduced as the overlap is enhanced.     

Oblique magneto-acoustic solitons in a rotating plasma

Weakly nonlinear magneto-acoustic waves propagating at an arbitrary angle to the external magnetic field in a rotating plasma are considered. A model equation (Ostrovsky's equation with positive dispersion) is derived from a set of basic magneto-hydrodynamic equations. Stationary solutions of this equation are obtained numerically and analyzed in detail theoretically. These include solitary-type solutions (solitons with monotonic and oscillating tails), complex multisolitons (bound states of coupled single solitons), as well as periodic waves. We emphasize that the positive dispersion, in contrast to the negative one, gives rise to solitary waves within the framework of Ostrovsky's equation.     

Collapse dynamics of a self-magnetized Langmuir plasma

We show that the set of generalized Zakharov equations which take into account the self-magnetic field reduce under certain circumstances to a generalized non-linear Schrödinger equation. We also that in the same approximation the self-magnetic field helps rather than hinders the Langmuir collapse.     

Control of interaction between femtosecond dark solitons in inhomogeneous optical fibers

In this paper, we present exact femtosecond one- and two-dark soliton solutions for a variable-coefficient higher-order nonlinear Schrödinger equation via modified Hirota method. The propagation and interaction of femtosecond dark solitons are investigated in inhomogeneous fiber systems. Elastic collision, bound oscillation and parallel propagation can be achieved in both Gaussian distributed parameter system and exponentially periodic distributed parameter system by choosing the appropriate distributed parameters and soliton parameters. The results may be beneficial to the realization of interaction control of femtosecond dark solitons in communication systems.     

Observation of interaction forces between one-dimensional spatial solitons in photorefractive crystals

We propagate two coherent and parallel beams of a He-Ne laser through a Bi(12)TiO(20) photorefractive crystal in the presence of drift nonlinearity. Our experimental results demonstrate that the beams attract or repel each other according to their initial phase difference. They attract each other when they are initially in phase and they repel each other when they are initially out of phase. These experimental results agree with numerical predictions recently published.     

Three-dimensional wake potential in a streaming dusty plasma

The oscillatory wake potential for a slowly moving or static test dust particulate in a finite temperature, collisionless and unmagnetized dusty plasma with a continuous flow of ions and dust particles has been studied. The collective resonant interaction of the moving test particle with the low-frequency and low-phase-velocity dust-acoustic mode is the origin of the periodic attractive force between the like polarity particulates along and perpendicular to the streaming ions and dust grains resulting into dust-Coulomb crystal formation. This wake potential can explain the three-dimensional dust-Coulomb crystal formation in the laboratory conditions.