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1.
Separate holographic screening soliton pairs in a biased series photorefractive crystal circuit 下载免费PDF全文
Holographic dark (bright) screening solitons are predicted
in one dimension for a series circuit consisting of two
photorefractive crystals connected electronically by electrode leads
in a chain with a voltage source. Each crystal can support a
holographic screening soliton. The two solitons are known
collectively as a separate holographic screening soliton pair with
three types: bright--bright, bright--dark and dark--dark. The
numerical results show that the two solitons in a soliton pair can
affect each other through a light-induced current and their coupling
can affect their spatial profiles under the limit in which the
optical wave has a spatial extent much less than the width of the
crystal. 相似文献
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This paper presents calculations for an idea in photorefractive spatial solitons, namely, a dissipative holographic soliton and a two-photon-Hamiltonian spatial soliton in one dimension form in an unbiased series photorefractive crystal circuit consisting of a single-photon photorefractive crystals and a two-photon one of which at least one must be photovoltaic. The two solitons are known collectively as a separate Holographic–Hamiltonian spatial soliton pair and there are two types: dark–dark and bright–dark if only one crystal of circuit is photovoltaic. The results show that the two-photon-Hamiltonian soliton in a soliton pair can affect the holographic one by light-induced current and the holographic soliton cannot affect the two-photon-Hamiltonian one. 相似文献
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Separate Holographic-Hamiltonian screening soliton pairs are predicted in a biased series photorefractive crystal circuit consisting of two photorefractive crystals connected electronically by electrode leads in a chain with a voltage source. The existence of four types of the separate soliton pairs: dark–dark, bright–dark, dark–bright and bright–bright in such a circuit is proved. Under the limit in which the spatial extent of the optical wave is much less than the width of the crystal, the Hamiltonian dark soliton can affect the other soliton by the light-induced current whereas the Hamiltonian bright soliton and holographic soliton cannot affect the other soliton in the soliton pair. 相似文献
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采用数值方法研究了在一个具有扩散效应的光伏光折变晶体中的非相干耦合的亮和暗光伏空间孤子对的偏转特性.结果表明,由于非相干相互作用,晶体中的一个亮孤子和一个暗孤子互相俘获,且两个孤子的中心沿着相同的轨迹移动.发现,当亮孤子的入射峰值强度不变时,通过调节暗孤子的入射背景强度可以控制亮孤子的偏转;当暗孤子的入射背景强度处于一个特殊值时,亮孤子的偏转被抑制,而当暗孤子的入射背景强度偏离这个特殊值时,亮孤子发生偏转.同样,当暗孤子的入射背景强度不变时,其偏转可以通过调节亮孤子的入射峰值强度来控制. 相似文献
6.
We present the observation of incoherent anti-dark photovoltaic solitons in LiNbO3:Fe crystal. This new class of soliton states involves bright photovoltaic solitons on a background beam meeting ?? > 1, where ?? is the ratio of background illumination photovoltaic constant to that of soliton beam. For ?? < 1, dark photovoltaic solitons are generated. Furthermore, this novel type solitons are investigated experimentally by injecting coherent light and partially coherent background of infinite extent. In case of spatial coherence of the background lower than the threshold of incoherent modulation instability, these results indicate that bright photovoltaic solitons can propagate in a stable fashion. 相似文献
7.
光折变明孤子的自偏转演化特性 总被引:4,自引:1,他引:3
利用一维稳态光折变空间光孤子的统一理论,研究了负载电阻对屏蔽、光伏和屏蔽光伏明孤子自偏转特性的影响。结果表明,无论加载电阻与否,这三种类型的光折变明孤子具有类似的自偏转特性,即孤子波沿一个抛物线轨迹运动。调节负载电阻可以改变孤子的偏转幅度,其中屏蔽光伏明孤子的可调范围最大。 相似文献
8.
Effect of temperature on the evolution of bright and dark screening—photovoltaic spatial solitons 下载免费PDF全文
We investigate theoretically the temperature effects on the evolution of both bright and dark screening-photovoltaic optical spatial solitons in biased photovoltaic-photocefractive crystals in the case of neglecting the diffusion process.For a stable bright or dark screening-photovoltaic soliton originally formed in a crystal at a given temperature,when the crystal temperature changes,it will evolve into another stable screening-photovoltaic soliton if the change is quite small,whereas it will become unstable or break down if the temperature change is large enough.The spatial shape of a stable screening-photovoltaic soliton can be reshaped by appropriately adjusting the crystal temperature. 相似文献
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在两种极限情况下求得了向列型液晶中(1+1)D空间光孤子的精确解析解。对非局域非线性项作近似计算,获得了光束的演化方程。在弱非局域情况下,直接积分得出单峰孤子解;强非局域情况下,用贝塞尔函数表示明孤子的解析解,本征值个数与峰的个数一致,预示了多峰明孤子的存在;这些结果与其它文献的精确数值解一致。并把所得解与双曲近似解析解进行了比较。 相似文献
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以折射率改变为正的光伏晶体为例,讨论在其中形成双色光光伏空间孤子的条件-一般而言,在满足上述条件的情况下,双色光可以形成双色光亮孤子、双色光暗孤子、一亮一暗孤子-对于一个波长的光(ray2)单独不能形成亮孤子(它的Glass系数与背景光的Glass系数之比R2小于1)的情况,如果再加上一束另一个波长的光(ray1),且其Glass系数与背景光的Glass系数之比R1大于1,则在一定条件下,这个双色光中两个颜色的光可以都形成亮孤子-还讨论了ray1的光强对孤子宽度的影响-
关键词:
双色光
光伏
空间孤子
全光开关 相似文献
15.
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
16.
The existence and coupling of grey–grey separate spatial solitons in a biased series photorefractive crystal circuit with both the linear and quadratic non-linearity is investigated in this paper. The numerical solution of the grey–grey separate spatial solitons is presented. The effect of coupling between the two separate spatial solitons and the influence on each soliton due to the input intensity and crystal’s temperature is analysed. Changing the intensity of the soliton in one crystal affects the soliton in both crystals due to flow of the light induced current through the circuit. Also, the effect of changing the temperature of one crystal affects the soliton in both crystals due to the coupling effect. The soliton width dependence on the temperature is different for each crystal. 相似文献
17.
Liu S Hu Y Zhang P Gan X Xiao F Lou C Song D Zhao J Xu J Chen Z 《Optics letters》2011,36(7):1167-1169
We demonstrate coherent interactions between spatial gap solitons in optically induced photonic lattices. Because of the "staggered" phase structures, two in-phase (out-of-phase) bright gap solitons can repel (attract) each other at close proximity, in contrast to soliton interaction in homogeneous media. A reversal of energy transfer direction and a transition between attractive and repulsive interaction forces can be obtained solely by changing the initial soliton separation relative to the lattice spacing. 相似文献
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Small-amplitudesolitonsinnonlinear-saturationglassfibersSmall-amplitudesolitonsinnonlinear-saturationglassfibers¥YUZhongyuan;... 相似文献
20.
Generalized Theory of One-Dimensional Steady-State Optical Spatial Solitons 总被引:1,自引:0,他引:1 下载免费PDF全文
We present a generalized soliton theory based on the one-dimensional generalized nonlinear Schroedinger equation,from which one can easily obtain the bright, dark, and grey soliton waveforms, and their existence curves. We show that the forming conditions of spatial solitons are directly dependent on the relationship between the index perturbation and the intensity, no matter whether the index perturbation is positive or negative. Some relevant examples are presented when the solitons are supported by the photoisomerization nonlinearity. 相似文献