Two-component coupled photovoltaic soliton pair in two-photon photorefractive materials under open circuit conditions

The existence and nonlinear dynamics of two-component incoherently coupled composite solitons in two-photon photorefractive materials under open circuit conditions have been investigated. In the steady-state regime, these incoherently coupled solitons can propagate in bright–dark, bright–bright and dark–dark configurations. These photovoltaic soliton families can be established provided that the carrier beams share the same polarization and wavelength. The influence of the gating beam on the dynamics of stable solitons is discussed. Numerical simulations show that these solitons are stable for small perturbation on amplitude.     

Photovoltaic spatial soliton pairs in two-photon photorefractive materials

We report the existence of incoherently coupled bright-bright steady state photovoltaic soliton pairs in two-photon photorefractive material under open circuit conditions. Based on WKBJ method and paraxial ray approximation, we have obtained coupled equations describing dynamical evolution of spatial soliton pairs. In the steady state regime, the present analysis leads to the identification of existence equation of bright-bright solitons, which captures a plethora of soliton pairs. We have undertaken linear stability analysis which shows that these solitons are stable.     

Photovoltaic solitons in two-photon photorefractive materials under open-circuit conditions

We present the evolution equation of one-dimensional spatial soliton in two-photon photorefractive media under open-circuit conditions. In the steady state regime, our solutions show that the dark and bright photovoltaic spatial solitons can be supported in two-photon photorefractive media under open-circuit conditions.     

闭路光伏光折变聚合物中非相干耦合亮-暗空间孤子对

为了得到闭路光折变有机聚合物中存在非相干耦合亮-暗光伏空间孤子对,采用数值模拟的方法,对稳态情况下两束互不相干的光束,在闭路光伏光折变有机聚合物中的传播进行了研究。结果表明,具有相同偏振和相同波长的两束互不相干的光束,可在光伏光折变有机聚合物中形成非相干耦合亮-暗光伏孤子对。在给定适当参量或扰动不太大的情况下,孤子对中的亮孤子和暗孤子都能在光伏光折变有机聚合物中稳定传播。研究结果可为光折变有机聚合物空间孤子理论的发展提供理论依据。     

空间非相干多分量光束构成的非相干耦合屏蔽孤子对

两束本身具有空间非相干性的非相干多分量光束可以在光折变介质中形成非相干耦合 屏蔽孤子对，利用相干密度法得到了亮 亮、暗 暗型耦合孤子对的解，并研究了构成 非相干孤子对分量光束的相干组分的传播特性. 关键词： 空间非相干多分量光束 耦合孤子对 相干密度 相干组分     

光折变聚合物中的小振幅空间光孤子(英文)

给出了稳态条件下光折变聚合物中的小振幅空间孤子的演化方程,得到了方程的暗、亮孤子解析解,并且给出了小振幅聚合孤子的宽度表达式。结果表明,光折变聚合物中存在着双曲正切形式的小振幅暗空间孤子和双曲正割形式的小振幅亮空间孤子,小振幅聚合孤子的宽度与外加电场成反比关系。     

光折变聚合物中的小振幅空间光孤子

给出了稳态条件下光折变聚合物中的小振幅空间孤子的演化方程,得到了方程的暗、亮孤子解析解,并且给出了小振幅聚合孤子的宽度表达式结果表明,光折变聚合物中存在着双曲正切形式的小振幅暗空间孤子和双曲正割形式的小振幅亮空间孤子,小振幅聚合孤子的宽度与外加电场成反比关系.     

Separate spatial holographic and two-photon-Hamiltonian soliton pairs in an unbiased series photorefractive crystal circuit

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.     

中心对称双光子光折变低振幅灰孤子时间特性

为了得到中心对称双光子光折变晶体中低振幅灰空间孤子时间特性的结果,基于中心对称光折变晶体中双光子光折变效应的理论模型,推导出了含时间参量的空间电荷场和光波动态演化方程.采用数值方法,得到了低振幅灰孤子强度包络和强度半峰全宽的时间演化特性.结果表明:初始阶段形成宽度较宽的孤子,其宽度随时间单调递减到一个最小值直至稳态孤子的形成;在相同的演化时间内,孤子半峰全宽随着孤子峰值强度与暗辐射比值的增大而变小.研究了不同时间下低振幅灰孤子动态演化特性.     

Temporal behavior of spatial solitons in centrosymmetric photorefractive crystals

We investigate theoretically the time behavior of spatial solitons in biased centrosymmetric photorefractive crystals. A one-dimensional time-dependent wave propagation equation in biased centrosymmetric photorefractive crystals is presented. It is shown that the bright solitons exist in both quasi-steady-state and steady-state regimes for high saturation values. When the intensity ratio is smaller than unity, the bright soliton width decreases monotonically to a minimum value toward steady state. Moreover, the time-dependent nonlinear wave equation exhibits only steady-state screening dark spatial solitons.     

Manakov solitons in centrosymmetric photorefractive crystals due to two-photon photorefractive effect

We present a theoretical study on incoherently coupled soliton pairs in two-photon centrosymmetric photorefractive crystals under steady-state conditions. It is shown that the bright-bright, dark-dark and bright-dark Manakov soliton pairs can be generated in two-photon centrosymmetric photorefractive crystals when the total intensity of two soliton components is much lower than the dark irradiance.     

低振幅双光子屏蔽光伏孤子的时间特性

为了得到低振幅双光子屏蔽光伏孤子时间特性的结果,采用数值模拟的方法对低振幅双光子屏蔽光伏孤子的时间特性进行了理论分析,得到了明和暗孤子时间特性的演化方程。结果表明:孤子的宽度随时间的演化单调递减到一个最小值直至稳态孤子的形成,在相同的演化时间内,孤子的半峰全宽随着孤子峰值强度和暗辐射比值的增大而变窄。     

双光子光折变晶体串联回路中独立全息屏蔽空间孤子对

为了得到双光子独立全息屏蔽空间孤子对的结果,基于光折变晶体中的两波耦合和双光子光折变效应,证明在由两块双光子光折变晶体和一个电压源通过导线连接组成的串联回路中存在全息亮(暗)屏蔽孤子。每块晶体中能支持一个全息屏蔽孤子,这两个孤子称为双光子独立全息屏蔽孤子对,有明-明、暗-暗和明-暗三种类型。数值计算结果表明,在光束的空间展宽远小于晶体宽度的极限条件下,孤子对中的两孤子通过光电流和相互耦合能影响到这些孤子的空间包络和动态演化特性。     

温度对双光子亮光伏空间孤子演化特性的影响

基于扩散效应及暗辐射强度对温度的依赖关系,研究了温度对双光子光伏光折变介质中亮光伏空间孤子动态演化及自偏转特性的影响。将亮孤子作为入射孤子波,采用数值方法求解孤波演化方程,结果表明:在给定温度下,双光子光折变介质中可以形成稳定的亮光伏空间孤子,当介质的温度变化不大时,孤子将克服较小的扰动而保持稳定的孤子传播,当温度变化足够大时,孤子将变得不稳定甚至崩溃;在一定温度范围内,孤子中心的自偏转距离随着温度的升高而增加,在特定温度下达到最大值,之后随着温度的升高而减小。     

Temporal behavior of low-amplitude dark spatial solitons in two-photon centrosymmetric photorefractive media

We investigate the temporal behavior of low-amplitude dark spatial solitons in biased centrosymmetric crystals with two-photon photorefractive effects. The expressions of time-dependent space-charge field and dynamical evolution equation are derived. The temporal behaviors of the intensity profiles and the intensity full width at half maximum (FWHM) of dark solitons are investigated by numerical method. The results indicate that a broad soliton is generated at the beginning, and as time evolves, the intensity width of solitons decrease monotonously to a minimum value toward steady state. Within the same propagation time, the higher the ratio of soliton peak intensity to the dark irradiation intensity is, the shorter the FWHM of dark solitons is.     

中心对称光折变晶体中非相干耦合空间孤子族

 为了得到中心对称光折变晶体中存在非相干耦合空间孤子族的结果,基于中心对称光折变晶体空间孤子的基本理论,推导出了中心对称光折变晶体中非相干耦合亮、暗和亮-暗混合空间孤子族空间归一化包络解的积分形式,并对其特性进行了数值模拟。结果表明：这种孤子族是由多束偏振方向和波长都相同的互不相干的光束耦合形成的,非相干耦合孤子族在中心对称光折变晶体中传播时,各分量成分光束都能稳定传播,当入射光束中只含有两分量时,空间孤子族退化为暗 暗、亮-亮和亮-暗空间孤子对。     

有分压电阻和e偏振非相干背景光辐照的光折变晶体中非相干耦合空间孤子对

为了得到光折变晶体中非相干耦合空间孤子对统一理论的结果,基于单光子光折变空间光孤子的基本理论模型,建立了稳态条件下有分压电阻和e偏振非相干均匀背景光辐照的单光子光伏光折变晶体中非相干耦合空间孤子对理论. 研究表明:这种孤子对是由两束偏振方向和波长都相同的互不相干光束耦合形成的, 孤子对两光束都能在晶体中稳定传播;当分压电阻、e偏振背景光、外加电场和光伏场取不同值时, 可获得14种光折变非相干耦合空间孤子对. 本文的结果对完善和充实光折变空间孤子理论体系有重要意义.     

有分压电阻和e偏振非相干背景光辐照的光折变晶体中非相干耦合空间孤子对

为了得到光折变晶体中非相干耦合空间孤子对统一理论的结果,基于单光子光折变空间光孤子的基本理论模型,建立了稳态条件下有分压电阻和e偏振非相干均匀背景光辐照的单光子光伏光折变晶体中非相干耦合空间孤子对理论.研究表明:这种孤子对是由两束偏振方向和波长都相同的互不相干光束耦合形成的,孤子对两光束都能在晶体中稳定传播;当分压电阻、e偏振背景光、外加电场和光伏场取不同值时,可获得14种光折变非相干耦合空间孤子对.本文的结果对完善和充实光折变空间孤子理论体系有重要意义.     

亮-暗非相干耦合光伏孤子对

对开路光伏介质中两束共线传播的互不相干光束的耦合作用进行了研究，发现在光伏效应的作用下，介质中可形成亮-暗非相干耦合空间孤子对，并对这种孤子对的物理特性进行了讨论。     

Temporal analysis of low-amplitude screening spatial solitons due to two-photon photorefractive effect

This paper investigates the temporal behavior of two-photon screening spatial solitons using a numerical technique. An expression for the time-dependent dynamical evolution is obtained. The results show that the width of bright solitons decreases monotonically to a minimum toward steady state value when the intensity ratio of the solitons is small, which is in low-amplitude regime. Within the same propagation time, the intensity width of solitons decreases with increase in soliton intensity ratio and with increase in external electric field. The formation time of solitons is independent of the intensity ratio of the solitons or the external electric field and is close to a constant determined by the dielectric relaxation time. The temporal properties of dark solitons are similar to those of the bright solitons.