【摘 要】
：
Wave propagation is studied in structures consisting of alternate left- and right-handed layers. Bragg gap and zero-n gap appear in different frequency regions of the structure. The periodicity of the structure is broken by simply reversing the order of t
【出 处】
：
ChineseOpticsLetters
论文部分内容阅读
Wave propagation is studied in structures consisting of alternate left- and right-handed layers. Bragg gap and zero-n gap appear in different frequency regions of the structure. The periodicity of the structure is broken by simply reversing the order of the layers in one half of the structure, resulting in defect modes located inside the zero-n gap and Bragg gap. These modes can be made very narrow by adding more layers in the structure. The defect mode located inside the zero-n gap is sensitive to the symmetry of the structure and insensitive to the angle ofincidence of the incoming radiation. Multiple modes are also generated inside the gaps by repeating the structural pattern. Thus, a simple structure can be used for single and multiple modes that are important for different applications.
其他文献
Brillouin spectroscopy is a powerful tool for measuring the mechanical properties of materials without contact. The sensitivity to mechanical changes that a Brillouin spectrometer can detect is determined by the precision to which a spectral peak can be l
研究了基于机器视觉的三维重建技术。利用普通的数码摄像机拍摄图片,通过摄像机定标、特征点检测和匹配、基础矩阵和本质矩阵计算来实现图像的三维重建。采用张正友标定方法的相机标定工具箱实现了相机的标定,利用尺度不变特征变换(SIFT)特征点的检测和匹配方法进行了图像特征点的检测和匹配,采用RANSAC算法计算基础矩阵,最后利用相机内参数和由基础矩阵获得的本质矩阵重建物体的特征点,并进行纹理贴图。实验结果表
A general method to realize arbitrary dual-band independent phase control is proposed and demonstrated in this paper. A double-layered C-shape reflective meta-atom is designed to realize independent phase control with high efficiency. As a proof of concep
介绍了体异质结聚合物太阳电池的基本原理, 并分析了限制体异质结有机太阳电池转化效率的因素。从提高激子的产生效率及其解离效率、电极对电荷的引出效率、电池的稳定性以及电池的光谱吸收范围四个方面, 综述了提高体异质结聚合物太阳电池能量转化效率的方法。
采用分步傅里叶法,通过数值模拟研究了饱和非线性介质中艾里孤子的产生与传输调控。单艾里光束入射时,在一定的初始振幅范围内可以产生稳定传输的呼吸式孤子。初始振幅增加时,孤子的强度增加,呼吸周期变短,但宽度基本保持不变。衰减系数增加时,孤子的平均峰值强度先增大后减小之后再增大,存在两个极值点。光束入射角度为负值时,形成左倾艾里孤子;光束入射角度为正值时,形成右倾艾里孤子。双艾里光束入射时,入射角同为负值可以减弱光束间的相互作用,入射角同为正值可以增强光束间的相互作用。此外,不同的入射角可以控制孤子或孤子对的传输
Exceptional points (EPs) are degeneracies of non-Hermitian operators where, in addition to the eigenvalues, the corresponding eigenmodes become degenerate. Classical and quantum photonic systems with EPs have attracted tremendous attention due to their un
报导了新激光分子顺式-C2H2F2六条远红外线的受激发射，它们的高转换效率达到了7%的理论极限值。用一组分子选择判据估算了这种分子产生远红外受激发射的效率。分析激光特性，增进了分子参量对高转换效率所起作用的进一步了解。本工作完善了这组选择判据，并可用来预测更多有效的激光分子。
A new kind of variable-length codes with good correlation properties for the multirate asynchronous optical code division multiple access (OCDMA) multimedia networks is proposed, called non-repetition interval (NRI) codes. The NRI codes can be constructed
采用粉料漂浮高温熔融法自制Nd3 掺杂硫系玻璃微球，研究了腔量子电动力学增强效应对稀土掺杂硫系玻璃微球荧光光谱的影响。把直径90.53 μm的硫系玻璃微球与锥腰直径1.02 μm的石英光纤锥耦合，将808 nm抽运激光导入微球，荧光光谱存在分立的共振峰。根据米氏散射理论公式，计算得到TE偏振态下基模的三个共振峰位置，确定了这三个共振峰的模式序数。增强因子η≈1122，这表明微球荧光自发辐射速率增强幅度为1122倍。在基模条件下对原增强因子公式进行近似化简，并利用近似公式进行估算得到η≈1167，误差为4%
俄勒冈研究生中心(Oregon graduate Center)的科学家们已经研制了一种测量云雾对激光束传播影响的实验装置。据物理学家R. Elliott说，介电液体的乳剂可用来模拟大气中水滴的多重散射。他指出，这些缩小的模拟云彩在雷达、遥感实验以及在卫星-潜艇通讯等方面可能是有用的，在这些场合，这种散射可以使光信号畸变。