在可光聚合介质中由于不连贯的白光的调制不稳定性而导致自发的图案形成
Ian B Burgess1, Whitney E Shimmell, Kalaichelvi Saravanamuttu
1Department of Chemistry, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4M1, Canada.
Journal of the American Chemical Society
|March 24, 2007
概括
由于聚合诱导的折射率变化,观察到白光束中自发的图案形成. 这些非线性效应导致自我捕获的光纤,在有机氧材料中产生微观结构.
科学领域:
- 非线性光学是非线性光学.
- 材料科学 材料科学 材料科学
- 光聚合的光聚合方式.
背景情况:
- 调制不稳定是非线性光学中的一个关键现象.
- 光束的自我聚焦和自我捕捉是由强度依赖的折射率驱动的.
- 光聚合材料提供了对光学性能的动态控制.
研究的目的:
- 为了研究在不连贯的白光下自发的图案形成.
- 探索光聚合介质中非线性光学效应的作用.
- 了解白光线丝的自我捕捉动力学.
主要方法:
- 一种不连贯的白光的宽均光束通过可光聚合的有机氧的传播.
- 通过强度依赖的折射率变化驱动的模式形成的观察.
- 分析光束分裂成自我捕获的细丝和由此产生的微观结构.
主要成果:
- 在不连贯的白光下通过调制不稳定性观察到的自发模式形成.
- 均的光束被分割成自我捕获的细丝 (76 +/- 3微米),没有衍射.
- 形成1D和2D阵列的自我陷入的结构 (叶片,圆柱状丝).
- 图案形成的速度与光学功率 (8.4-59.8mW) 反比例.
- 丝保留了白光光谱组成,证明了集体波段的参与.
- 永久的微观结构,包括道波导,形成在有机.
结论:
- 在非线性聚合条件下,自陷白光丝是最稳定的传播模式.
- 在这种介质中形成的模式永久地改变了它的微观结构,创造了通道波导.
- 这些发现与非线性白光传播的理论模型以及在连贯/部分连贯光中的实验观测相一致.
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