arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 1909.11263nlin.SImath-phmath.MP
收藏

具有非零边界条件的修正Landau-Lifshitz方程的Riemann-Hilbert问题

Riemann-Hilbert problem for the modified Landau-Lifshitz equation with nonzero boundary conditions

Jin-Jie Yang, Shou-Fu Tian

摘要:

本文系统地研究了无穷远处具有非零边界条件的修正Landau-Lifshitz(mLL)方程的矩阵Riemann-Hilbert问题.与零边界条件的情况不同,在直接散射过程中出现了双值函数。为了建立Riemann-Hilbert(RH)问题,需要进行适当的修改,即引入仿射变换,将Riemann曲面转换为复平面。在直接散射问题中,详细讨论了Jost函数和散射矩阵的解析性、对称性和渐近性。在此基础上,建立了单极点和双极点的离散谱、残差条件、迹线公式和θ条件。反问题通过由Jost函数和散射系数形成的矩阵RH问题求解。最后,给出了无反射势mLL方程几个典型孤子解的动力学行为,进一步研究了孤子波的结构。此外,还对这些孤子解的一些显著特征进行了图解分析。根据解析解,讨论了各参数对孤子波和呼吸子波动力学的影响,并提出了控制这种非线性现象的方法。

英文摘要:

We study systematically a matrix Riemann-Hilbert problem for the modified Landau-Lifshitz (mLL) equation with nonzero boundary conditions at infinity. Unlike the zero boundary conditions case, there occur double-valued functions during the process of the direct scattering. In order to establish the Riemann-Hilbert (RH) problem, it is necessary to make appropriate modification, that is, to introduce an affine transformation that can convert the Riemann surface into a complex plane. In the direct scattering problem, the analyticity, symmetries, asymptotic behaviors of Jost functions and scattering matrix are presented in detail. Furthermore, the discrete spectrum, residual conditions, trace foumulae and theta conditions are established with simple and double poles. The inverse problems are solved via a matrix RH problem formulated by Jost function and scattering coefficients. Finally, the dynamic behavior of some typical soliton solutions of the mLL equation with reflection-less potentials are given to further study the structure of the soliton waves. In addition, some remarkable characteristics of these soliton solutions are analyzed graphically. According to analytic solutions, the influences of each parameters on dynamics of the soliton waves and breather waves are discussed, and the method of how to control such nonlinear phenomena are suggested.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑