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61.
We address the existence of surface solitons at an interface in a defocusing cubic medium with an imprinted one-dimensional (1D) composite Bessel optical lattice. This setting is composed of two Bessel lattices with different orders and different modulation depths, separated beside both sides of an interface. Stability analysis and numerical propagation simulations prove that solitons supported by the model are dynamically stable in the entire domain of their existence. The order of lattice determines the shape of soliton, and the amplitude of soliton depends on the lattice modulation depth. The experimental realization of the scheme is also proposed. Our results may provide another effective way of controlling the shapes of surface solitons and thus their evolutions by introducing a new freedom degree. 相似文献
62.
We systematically investigate the motion of slowly moving
matter--wave gap solitons in a nonlinear potential, produced by the
weak random spatial variation of the atomic scattering length. With
the weak randomness, we construct an effective-particle theory to
study the motion of gap solitons. Based on the effective-particle
theory, the effect of the randomness on gap solitons is obtained, and
the motion of gap solitons is finally solved. Moreover, the analytic
results for the general behaviours of gap soliton motion, such as the
ensemble-average speed and the reflection probability depending on
the weak randomness are obtained. We find that with the increase of
the random strength the ensemble-average speed of gap solitons
decreases slowly where the reduction is proportional to the variance
of the weak randomness, and the reflection probability becomes
larger. The theoretical results are in good agreement with the
numerical simulations based on the Gross--Pitaevskii equation. 相似文献
63.
在色散位移光纤中,研究了三阶色散影响下同相和反相二阶孤子之间的互作用,分析了同相和反相二阶孤子对衰变后时域波形和频域频移的变化,发现三阶色散使二阶孤子分裂出一大一小两个不同振幅的基阶孤子,并彼此分离,但孤子对中心频率频移量却减小。通过采用非线性增益控制的方法可以有效抑制二阶孤子间的互作用,使孤子保型传输而不发生衰变。同时通过周期性改变三阶色散系数,可以减小三阶色散的不利影响,抑制孤子中心频率的频移,使孤子对不偏离原来时间槽,稳定孤子传输。 相似文献
64.
Inverse scattering method and soliton solutionfamily for the Einstein--Maxwell theory with multiple Abelian gauge fields
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A Hauser-Ernst-type extended hyperbolic complex linear system given in our previous paper [Gao Y J 2004 Chin. Phys. 13 602] is slightly modified and used to develop a new inverse scattering method for the stationary axisymmetric Einstein-Maxwell theory with multiple Abelian gauge fields. The reduction procedures in this inverse scattering method are found to be fairly simple, which makes the inverse scattering method be fine and effective in practical application. As an example, a concrete family of soliton solutions for the considered theory is obtained. 相似文献
65.
Adomian decomposition method and Padé approximants for solving the Blaszak--Marciniak lattice
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The Adomian decomposition method (ADM) and Pade approximants are combined to solve the well-known Blaszak-Marciniak lattice, which has rich mathematical structures and many important applications in physics and mathematics. In some cases, the truncated series solution of ADM is adequate only in a small region when the exact solution is not reached. To overcome the drawback, the Pade approximants, which have the advantage in turning the polynomials approximation into a rational function, are applied to the series solution to improve the accuracy and enlarge the convergence domain. By using the ADM-Pade technique, the soliton solutions of the Blaszak-Marciniak lattice are constructed with better accuracy and better convergence than by using the ADM alone. Numerical and figurative illustrations show that it is a promising tool for solving nonlinear problems. 相似文献
66.
We experimentally demonstrate amplitude squeezed soliton utilizing intensity-dependent self-phase modulation in an asymmetric Sagnac interferometer.The system.whose components are connected via ferrule connector/physical connection(FC/PC)fiber connectors,constitutes all-fiber configuration to generate squeezed soliton.Soliton amplitude reduction measured by homodyne detection is near 4.0 dB below the shot-noise level.Optimal squeezing fields in both simple and compact all-fiber configuration are obtained. 相似文献
67.
We present a new improvement to the Alekseev inverse scattering method. This improved inverse scattering method is extended
to a double form, followed by the generation of some new solutions of the double-complex Kinnersley equations. As the double-complex
function method contains the Kramer-Neugebauer substitution and analytic continuation, a pair of real gravitation soliton
solutions of the Einstein’s field equations can be obtained from a double N-soliton solution. In the case of the flat Minkowski
space background solution, the general formulas of the new solutions are presented.
相似文献
68.
ZHAO Hong BAI Cheng-Lin 《理论物理通讯》2004,42(10)
Using the extended homogeneous balance method, we obtained abundant exact solution structures of the (3 1 )-dimensional breaking soliton equation. By means of the leading order term analysis, the nonlinear transformations of the (3t1)-dimensional breaking soliton equation are given first, and then some special types of single solitary wave solutions and the multisoliton solutions are constructed. 相似文献
69.
Optical solitary waves that propagate in a Kerr medium exhibiting a power-law nonlocal response are studied analytically. The first-principles stability analysis based on quantum field theory shows that within the whole range of the exponent (the fractal dimension) the solitary wave can be stabilized. 相似文献
70.
首先研究了非线性饱和光纤中各阶孤子存在的幅值范围,与标准非饱和情况的非线性薛定谔孤子非常不同,即一阶孤子幅值范围是1.4≤N≤∵.0,二阶孤子为4.0≤N≤♀.0,三阶孤子为7.0≤N≤≤15.0,并分析了各阶孤子的传输特性,最后研究了双一阶孤子相作用的若干特点,明确了五个方面的特性。 相似文献