Negative Refraction in Photonic Crystals
Negative Refraction in Photonic Crystals
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DOI：
10.4028/www.scientific.net/ast.55.91
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发表时间：
2008-09
期刊：
影响因子：
5
通讯作者：
T. Baba;T. Asatsuma;T. Matsumoto
中科院分区：
文献类型：
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作者：
T. Baba;T. Asatsuma;T. Matsumoto
光子晶体是一种多维周期光栅，其光的传播主要受布拉格衍射的支配，这种衍射在晶体的平面上表现为折射。根据光子能带理论，可以对从正到负的完全或部分服从斯涅尔定律的折射角进行调整。负折射使新的棱镜，准直，和镜头效果。由于光子晶体通常由两种透明介质组成，这些效应发生在无吸收频率，为自由空间光学提供了显著的设计灵活性。光子晶体板是一种具有二维气孔阵列的高折射率薄膜，必须仔细设计以避免不必要的反射和衍射。基于负折射的光聚焦形成光源的平行图像，便于用于波长解复用的光学耦合器和聚光透镜。结合棱镜和透镜效应，可以设计出紧凑的波长解复用器。
Photonic crystals are multidimensional periodic gratings, in which the light propagation is dominated by Bragg diffraction that appears to be refraction at the flat surfaces of the crystals. The refraction angle from positive to negative, perfectly or only partially obeying Snell’s law, can be tailored based on photonic band theory. Negative refraction enables novel prism, collimation, and lens effects. Because photonic crystals usually consist of two transparent media, these effects occur at absorption-free frequencies, affording significant design flexibility for free-space optics. The photonic-crystal slab, a high-index membrane with a two-dimensional airhole array, must be carefully designed to avoid unwanted reflection and diffraction. Light focusing based on negative refraction forms a parallel image of a light source, facilitating optical couplers and condenser lenses for wavelength demultiplexing. A compact wavelength demultiplexer can be designed by combining the prism and lens effects.