复色光伏孤子的稳定性  

Stability of photovotaic spatial soliton with two-wavelength components

作　　者：欧阳世根[1] 江德生[1] 佘卫龙[1] 

机构地区：[1]中山大学光电材料与技术国家重点实验室,广州510275

出　　处：《物理学报》2004年第9期3033-3041,共9页Acta Physica Sinica

基　　金：国家自然科学基金 (批准号 :10 0 740 82 );广东省自然科学基金 (批准号 :0 0 1192 ;0 3 15 67)资助的课题~~

摘　　要：给出求解复色孤子半高宽的近似方法 ,该方法对分析复色光束的演化提供一个定性的基础 .进一步的数值模拟结果表明 ,当入射双曲正割光束满足复色光伏孤子半高宽与中心光强的关系时 ,双曲正割光束在晶体中的传播就非常接近孤子 ,表明复色光伏孤子对于小的微扰是稳定的 .此外 ,复色光伏孤子对于小的轴偏离具有较好的稳定性 ;复色光伏孤子对因温度微扰引起折射率变化的情况也具有较好的稳定性 .一般情况下 ,初始光强分布接近复色光伏孤子光强分布的两束光的光强在传播过程中不断地起伏 ,形成呼吸状结构 ,但如果入射面处的光强明显偏离孤子的光强分布时 ,入射光束就会随着传播而不断扩展 。An approximate method is presented to calculate the full width at half maximum(FWHM) of photovoltaic(PV) spatial solitons(PVSSs) with two wavelengths component. An advanced numerical analysis indicates that two coaxial hyperbolic secant beams, provided that they satisfy the functional relations of FWHM with amplitudes of this type of PVSS, will be very close to solitons when they propagate in PV crystals. Besides, this type of PVSS tends to be stable against small axial perturbations and small refractive index perturbations due to variations of temperature of the crystal. However, if the profiles of intensity of two coaxial signal beams with different wavelengths differ mildly from those of PVSS, the two beams will tend to experience cycles of compression and expansion; and if the profiles of intensity of the signal beams differ significantly from those of PVSS, these two signal beams will diffuse endlessly.

关 键 词：复色光伏空间孤子 稳定性 数值模拟 中心光强 微扰理论 光强分布 

分 类 号：O437[机械工程—光学工程]