共查询到18条相似文献,搜索用时 109 毫秒
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用数值方法分析了平行传播异色光伏暗孤子之间及亮-暗孤子之间的相互作用.结果表明,光伏暗孤子共轴传播能在有限的距离内保持准孤子形态,靠近传播时存在着相互吸引的作用 ,而相距较远传播时表现为一孤子暗区使另一孤子的缓变光场部分发生局部会聚作用.光伏暗孤子与亮孤子的相互作用随距离的不同可使亮孤子光强分布变尖锐或变平缓,以及使亮孤子发生能量转移.从两束信号光共同引起折射率波导这一物理机理对光伏孤子这些相互作用给出定性物理解释.
关键词:
光伏空间孤子
暗孤子
亮孤子
相互作用 相似文献
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基于相干密度理论,数值地研究了在饱和对数非线性介质中多个部分非相干光空间孤子之间的相互作用. 数值结果表明,在非相干参量较小情况下,非相干光孤子的相互作用与相干光孤子的相互作用规律较类似. 当非相干参量较大时,强的非相干性模糊了孤子之间的相位关系,孤子间的相互作用主要以非相干相互吸引作用为主. 特别是在非相干参量较大而且孤子初始相对相位差为π的情况下,多个部分非相干光孤子可并行传播形成稳定的阵列孤子. 利用多个非相干光孤子的不同相互作用形态写入各种阵列波导,为实现光控制光、导向光提供了一种可能性.
关键词:
多个部分非相干光空间孤子
空间光孤子的相互作用
相干密度理论
饱和对数非线性 相似文献
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采用数值方法研究了三个呈非对称分布的相干光伏空间孤子碰撞相互作用.结果表明,随着信号光的入射角度在一定范围内逐渐改变,三个孤子在晶体中碰撞后会产生孤子的分裂或湮没现象.当孤子碰撞后出现分裂或湮没时,若保持孤子的碰撞角度不变,改变其中任意一个孤子的初始相对相位,孤子的碰撞行为也将随之迅速改变,产生新的孤子分裂、湮没或其他碰撞现象.另外,研究结果还表明,作为具有不可积哈密顿系统特性的光伏孤子,其小角度碰撞过程中动量和能量仍然是守恒的.
关键词:
光伏孤子
非对称碰撞
分裂
湮没 相似文献
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飞秒暗孤子间相互作用的数值研究 总被引:7,自引:1,他引:6
通过数值模拟对飞秒暗孤子间的相互作用进行了研究,并且同飞秒亮孤子和皮秒暗孤子分别进行了比较,结果表明:同飞秒亮孤子相比,飞秒暗孤子间的相互作用比较小,前者表现为相互吸引、碰撞、合二为一,然后相互排斥,不具有周期性;而后者从一开始就相互排斥,且这种排斥作用较亮孤子来说相当微弱,同样也不具有周期性。此外,数值模拟的结果还表明,飞秒暗孤子间的相互作用同皮秒尺度下暗孤子间的相互作用基本一致,并且通过计算表明,飞秒暗孤子间的相互作用在一定范围内仍可利用皮秒尺度下暗孤子间相互作用的经验公式。但是,数值模拟结果显示,两孤子的初始间距越小,由经验公式计算结果所带来的误差就越大。 相似文献
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We present an analytical and numerical investigation of the propagation of spatial solitons in a nonlinear waveguide with ramp linear refractive index profile (ramp waveguide). For the propagation of a single soliton beam in a ramp waveguide, the particle theory shows that the soliton beam follows a parabolic curve in the region where the linear refractive index increases and a straight line outside the waveguide. The acceleration of the soliton depends on the beam intensity: higher amplitude solitons experience higher acceleration. Numerical calculations using an implicit Crank–Nicolson scheme confirm the result of the particle theory. Combining these propagation properties with the theory about bound-N-soliton, we study the break up of such a bound-N-soliton in a ramp waveguide. In a ramp waveguide, a bound-N-soliton will always be splitted into N independent solitons with the higher amplitude soliton emitted first. The amplitude of the separated solitons after break up are calculated using the soliton theory as if the solitons are independent. Numerical simulations show that the results agree quite well with this theoretical prediction, indicating that the interaction during break up has only little influence. 相似文献
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We present an analytical and numerical investigation of the propagation of spatial solitons in a nonlinear waveguide with
ramp linear refractive index profile (ramp waveguide). For the propagation of a single soliton beam in a ramp waveguide, the
particle theory shows that the soliton beam follows a parabolic curve in the region where the linear refractive index increases
and a straight line outside the waveguide. The acceleration of the soliton depends on the beam intensity: higher amplitude
solitons experience higher acceleration. Numerical calculations using an implicit Crank-Nicolson scheme confirm the result
of the particle theory. Combining these propagation properties with the theory about bound-N-soliton, we study the break up of such a bound-N-soliton in a ramp waveguide. In a ramp waveguide, a bound-N-soliton will always be splitted intoN independent solitons with the higher amplitude soliton emitted first. The amplitude of the separated solitons after break
up are calculated using the soliton theory as if the solitons are independent. Numerical simulations show that the results
agree quite well with this theoretical prediction, indicating that the interaction during break up has only little influence.
On Leave from Jurusan Matematika, Universitas Brawijaya, Jl. MT Haryono 167 Malang Indonesia. 相似文献
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采用Petviashvili迭代法对光诱导平面波导阵列中的一维离散空间光孤子进行求解,利用分步束传播法对离散空间光孤子间的相干相互作用进行了详细的数值模拟.探讨了离散孤子间的相位差、孤子光强、波导阵列写入光的强度和周期以及外加电场对相互作用过程的影响.结果表明:离散孤子间的相位差对相互作用的影响与连续介质中的情况类似,不同相位差情况下的相互作用也表现为吸引、排斥以及能量转移等现象.同时,离散孤子间的相干相互作用过程(如融合距离和排斥间距等)均会受到孤子光强、波导阵列写入光的强度和周期以及外加电场大小的影响
关键词:
光诱导平面波导阵列
离散空间光孤子
相干相互作用 相似文献
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应用等效粒子近似方法研究了光学空间孤子在带有局域和非局域非线性横向非均匀介质中的传输动力学行为.发现孤子在传播过程中横向的周期性振荡.折射率调制幅度和波导的归一化宽度决定了振荡周期的大小.介质的非局域对振荡振幅有着较小的影响.模拟了孤子传输过程,所得数值结果与理论分析符合很好.此外,模拟传输还发现多孤子束缚态能够在这个模型中稳定传播.这种振荡特性或许可以应用于光学路由器、转换器、开关等. 相似文献
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Oscillatory behavior of spatial soliton in a gradient refractive index waveguide with nonlocal nonlinearity 总被引:1,自引:0,他引:1
Oscillatory behavior of spatial solitons in a transverse parabolic gradient refractive index distribution (GRIN) waveguide with both local and nonlocal nonlinearity is investigated. Dynamics of such solitons are analyzed by the effective-particle approach method. For weak nonlocal nonlinearity, solitons oscillate in transverse direction periodically during propagation. The normalized width and maximum of refractive index variation of the waveguide play a key role in determining the oscillating period while the position of soliton oscillatory center is slightly influenced by the nonlocal nonlinearity. Stronger nonlocal nonlinearity leads to instability of the oscillatory solitons. Furthermore, the dynamics of the solitons are simulated numerically and good agreements are obtained between the analysis and numerical results. This behavior may be used in all-optical routers, switches etc. PACS 42.65.Tg; 42.65.Jx; 42.65.Wi 相似文献
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线性聚焦和线性散焦效应对空间光孤子间相互作用的影响 总被引:2,自引:2,他引:0
考虑非均匀一维自聚焦介质的横向不均匀性,利用非线性薛定谔方程满足的守恒律给出了相邻空间孤子间隔的解析式,并对空间孤子之间的相互作用进行了数值模拟.结果表明,线形聚焦效应增强了空间孤子之间的相互作用;而线形散焦效应减弱了空间孤子之间的相互作用.当不考虑介质横向不均匀时,空间孤子之间发生周期性的碰撞.线性散焦效应使相邻空间孤子之间的间隔随传输距离发生周期性的变化,但孤子之间并不发生碰撞.线性聚焦效应使相邻空间孤子随传输距离发生周期性的碰撞,线性聚焦效应具有压制损耗使相邻空间孤子间隔变大的作用. 相似文献
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The propagation and interaction of nonlocal incoherent white-light solitons in strongly nonlocal kerr media is investigated. Numerical simulations show that the interaction properties of nonlocal incoherent white-light solitons are different from the case in local media. The interactions of nonlocal incoherent white-light solitons are always attractive independent of their relative phase, while the other parameters such as the extent of nonlocality and the input power have a great impact on the soliton interactions. Pertinent numerical examples are presented to show their propagation and interaction behaviour further. 相似文献
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Aavishkar Katti 《Optical and Quantum Electronics》2018,50(6):263
Characteristics of propagation of bright screening solitons are studied in a photorefractive waveguide. The investigation is performed under paraxial wave approximation and Wentzel–Kramers–Brillouin–Jefferys approximation. A Gaussian ansatz for the soliton shape is used instead of the numerical solutions. The planar waveguide structure intensifies the self-focussing while decreasing the minimum or threshold power required for self trapping. The waveguide structure embedded in the crystal can self trap a soliton of power lower than the threshold power. As the waveguide parameter increases, minimum required power to self trap the beam decreases. The existence of bistable states is also predicted. Four regimes of power are identified in which the solitons behaviour is studied. Propagation of screening solitons in a photorefractive waveguide is studied in the absence of the photovoltaic and pyroelectric effect for the first time. 相似文献