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1.
温度对双光子独立明-暗空间屏蔽孤子对稳定性的影响 总被引:2,自引:2,他引:0
在忽略损耗和扩散的情况下,采用数值方法研究温度对串联双光子光折变晶体回路中独立明-暗屏蔽孤子对演化和稳定性的影响.结果表明:在给定温度下晶体回路中形成稳态明-暗孤子对,当一个晶体的温度改变且温度变化不大时,另一块晶体中支持的孤子将转变为另一个稳态孤子;当温度变化过大时,这个孤子将变得不稳或发生周期性的压缩或膨胀甚至崩溃.在独立屏蔽空间孤子对中,暗孤子对温度的敏感程度比明孤子强. 相似文献
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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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对外加电场光折变有机聚合物串联回路中独立空间孤子对进行了理论研究,导出了在光折变有机聚合物串联回路中两光束传播的耦合方程,证明了串联回路中存在暗-暗、明-暗和明-明三种独立空间孤子对.在光束的空间展宽远小于有机聚合物宽度的极限条件下,暗-暗孤子对之间孤子入射光强的改变可相互影响到对方的包络和动态演化.对于明-暗孤子对,暗孤子通过光电流能影响明孤子,但明孤子不能影响暗孤子.明-明孤子对之间没有影响.
关键词:
非线性光学
光折变效应
光折变聚合物
空间孤子对 相似文献
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We investigate theoretically the dark soliton crystal temperature effect on the deflection of the bright one in a bright–dark soliton pair which is formed in a serial non-photovoltaic photorefractive crystal circuit. Our numerical results show that the spatial shift of the bright soliton changes with the temperature of the dark one crystal and varying the temperature of the dark soliton crystal can influence the deflection strongly. The temperature dependence of the deflection process is further studied by perturbation technique and the results are found to be good agreement with that obtained by numerical method. Relevant examples are provided. 相似文献
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The dynamical evolution and stability of
bright dissipative holographic solitons in biased photorefractive materials
in which the self-trapping beam obtains a gain from the pump beam via two-wave
mixing has been investigated numerically. Results show that these solitons are stable relative to small
perturbations. Adjusting some system parameters, such as the bias field and
the angle between beams, can easily control the generation of such solitons.
Potential applications in optical switches or repeaters are discussed. 相似文献
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The coupling effect and stability property of symmetric bright holographic soliton pairs have been investigated numerically. Results show that when any one of the two solitary beams from a pair is perturbed in amplitude or width, both beams will be affected by such a perturbation via the coupling effect between the beams, thus resulting in both beams propagating in the medium without a constant shape; however, these two solitary beams are still stable against small perturbations. When both solitary beams from a pair are perturbed simultaneously in amplitude, for some given absolute values of the perturbations, the two beams are stable against these perturbations if both beams are perturbed with the same sign, whereas are unstable with the different signs. When the two beams are simultaneously perturbed in width, both beams exhibit their stability property similar to that when only one beam is perturbed no matter whether both perturbations have the same or different signs. 相似文献
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对有外加电场的双光子光伏光折变晶体中两束偏振方向和波长都相同的互不相干光束的耦合进行研究,给出产生亮-暗双光子光折变屏蔽光伏孤子对需满足的条件.以Cu:KNSBN晶体作为研究对象,选取α=117.3,β=83.79,η=1.5×10-4,σ=104,δ=0.005,r=10时,给出双光子光折变晶体中的非相干耦合亮-暗屏蔽光伏孤子对2个孤子分量光强的空间分布,证明有外加电场的双光子光伏光折变晶体中存在非相干耦合亮-暗屏蔽光伏孤子对,指出孤子对是由偏振态和波长都相同的两束互不相干光形成的,当外加电场方向和晶体中光伏电场的方向与晶体光轴方向相同时,双光子光折变晶体中可支持亮孤子峰值光强稍大于暗孤子最大光强的非相干耦合亮-暗孤子对,当外加电场方向和晶体中光伏电场的方向与晶体光轴方向相反时,双光子光折变晶体中可支持亮孤子峰值光强稍小于暗孤子最大光强的非相干耦合亮-暗孤子对. 相似文献
9.
根据光波耦合方程及亮-暗孤子对解,对稳态情况下多束互不相干的光束在有外加电场的双光子非光伏光折变晶体中的传播进行分析,给出产生亮-暗双光子光折变屏蔽光伏孤子族需满足的条件。证明有外加电场双光子非光伏光折变晶体中存在非相干耦合亮-暗混合屏蔽孤子族,孤子族由偏振态和波长都相同的多束互不相干的光形成。当外加电场方向和晶体光轴方向相同时,双光子光折变晶体可支持亮孤子族总峰值光强稍大于暗孤子族总峰值光强的的非相干耦合亮-暗混合孤子族,当外加电场方向与晶体光轴方向相反时,双光子光折变晶体可支持亮孤子族总峰值光强稍小于暗孤子族总峰值光强的非相干耦合亮-暗混合孤子族。 相似文献
10.
LIU Jinsong 《Chinese Journal of Lasers》2001,10(5):347-352
1 Introduction Spatialsolitonsinphotorefractivemediahaveattractedmuchinterestinthepastfewyears[1~ 10 ] .Atpresent,threetypesofscalarsolitons ( quasi steady state[1~ 3 ] ,screening[4~ 8] andphotovoltaicsolitons[9~ 10 ] )havebeen predictedandfound .Sofar ,photovoltaicsolit… 相似文献
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A universal theory of steady-state one-dimensional photorefractive spatial solitons is developed which applies to the steady-state one-dimensional photorefractive solitons under various realizations, including the screening solitons in a biased photorefractive medium, the photovoltaic solitons in open- and closed-circuit photovoltaic-photorefractive media and the screening-photovoltaic solitons in biased photovoltaic-photorefractive media. Previous theories advanced individually elsewhere for these solitons can be obtained by simplifying the universal theory under the appropriate conditions. 相似文献
12.
证明了在加外电场的光折变晶体中存在非对称全息空间光孤子对,其特征是孤子对中的两个 孤子具有相同的宽度、不同的振幅.给出了这种孤子对的存在曲线,其中存在三个具有不同 特征的区域:对于给定的外加电场来说,当孤子对中两个孤子的入射峰值强度之和与背景光 强度之比足够大或者足够小时,孤子宽度强烈依赖于这个比值,而在此中间的一段区域,孤 子宽度几乎不随这个比值而变化.非对称情况下这个中间区域的范围比对称情况的窄.
关键词:
空间光孤子
光折变非线性光学
全息光栅 相似文献
13.
为了得到有偏压的中心对称双光子光折变晶体中存在多变量空间灰孤子的结果,基于中心对称双光子光折变晶体中空间灰孤子的基本理论,采用数值方法推导出了中心对称双光子多变量空间灰孤子归一化包络解的积分形式,并对其特性进行研究。结果表明:这种多变量空间灰孤子是由多束偏振方向和波长都相同的互不相干光束耦合形成的。当多变量空间灰孤子只包含有1个或2个光束分量成分时,它自动退化到中心对称双光子空间灰孤子或中心对称双光子非相干耦合灰 灰空间孤子对的情况。当这一多变量空间灰孤子在有偏压的中心对称双光子光折变晶体中传播时,各分量成分光束都能稳定传播。 相似文献
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Based on the temperature dependence of two-wave mixing, temperature effects on the dynamical evolution and stability of rigid screening (RS) bright solitons in a photorefractive dissipative system based on two-wave mixing have been investigated numerically. Our results indicate that the stability of bright RS solitons depends strongly on the crystal temperature. The RS solitons are stable to small temperature perturbations. They will not evolve into stable rigid screening solitons, however, and their intensity and width vary with the propagation distance if the temperature deviation is large enough. The potential applications of the temperature properties of these RS solitons in optical attenuators or repeaters are discussed. 相似文献
19.
We present a theoretical analysis of the stability of screening-photovoltaic (SP) spatial solitons in biased photovoltaic-photorefractive materials in the case of neglecting the loss of the material and the effect of diffusion. When an incident optical beam is a SP soliton, this beam propagates along a linear path with its shape kept unchanged. When the maximum amplitude, width and functional form of an incident optical beam are slightly different from those of a SP soliton, the beam reshapes itself and tries to evolve into a solitary wave after a short distance. That is, these SP solitons are stable against small perturbations. However, optical beams that significantly differ from SP soliton solutions tend to experience larger cycles of compression and expansion, and their maximum amplitudes oscillate with propagation distances. The larger the perturbations, the stronger the oscillation. 相似文献
20.
研究了基于双光束耦合的光折变耗散系统中全息明孤子的温度演化特性.数值计算结果表明,晶体温度与刚性全息孤子的稳定性密切相关.在一定温度下,全息孤子能在晶体中传播足够远的距离;当晶体温度漂移不大时,入射孤子能演化成稳定的全息孤子继续传播;而当晶体温度变化足够大时,孤子波强度随传播距离增加或减小,入射孤子不能以稳定的全息孤子态传播.讨论了将刚性全息孤子的温度特性应用于光学衰减、中继器件的可能性.
关键词:
空间光孤子
光折变非线性光学
耗散系统
全息聚焦 相似文献