【摘 要】
：
We propose an ultra-wideband optical diode device based on two-dimensional square-lattice photonic crystals. For the device, the odd mode is completely transmitted in one direction and converted to the fundamental even mode, but completely reflected in th
【机 构】
：
CollegeofInformationEngineering,ZhejiangUniversityofTechnology,Hangzhou310023,ChinaStateKeyLaborator
【出 处】
：
ChineseOpticsLetters
论文部分内容阅读
We propose an ultra-wideband optical diode device based on two-dimensional square-lattice photonic crystals. For the device, the odd mode is completely transmitted in one direction and converted to the fundamental even mode, but completely reflected in the other direction. The operation bandwidth of the device is preserved within a rather wide range of frequencies, which is over 6.5% of the central frequency. A directional coupler and 90° bend are utilized as the composite function device with mode filter and mode converter. It is possible that the photonic crystal device can help to construct on-chip optical logical devices and benefit greatly to the optical systems with multiple spatial modes.
其他文献
Germinated brown rice (GBR) is rich in gamma oryzanol which increase its consumption popularity, particularly in the health food market. The objective of this research was to apply the near infrared spectroscopy (NIRS) for evaluation of gamma oryzanol of
基于柯林斯（Collins）积分公式，导出了高斯-谢尔模型(GSM)光束在有色差的分数傅里叶变换(FRFT)系统中的光谱传输表达式，并以Lohmann Ⅱ型系统为例，通过数值计算与分析，研究了色差大小、分数傅里叶变换阶数、以及相对横向坐标对输出面归一化光谱和相对谱移动的影响。研究表明，相对谱移动随FRFT阶数的变化而改变，色差的大小会影响相对谱移动的大小、光谱跃变发生的位置以及光谱跃变量的大小；相对谱移动随色差的变化而改变，在不同阶数的FRFT系统中，相对谱移动随色差的变化规律各不相同。此外，归一化的光谱
We present a sparse Bayesian reconstruction method based on multiple types of a priori information for multispectral bioluminescence tomography (BLT). In the Bayesian approach, five kinds of a priori information are incorporated, reducing the ill-posednes
本文就BNN主轴截面通光的情形,将温度和角度作为两个独立变量对倍频过程进行了分析,得到谐波功率与温度和角度的近似关系、谐波各方向的折射率随温度的变化关系以及在完全位相匹配情况下温度与角度的关系。实验结果与理论符合得较好。
结合延迟容忍网络(DTN)架构中束协议/利克里德传输协议(BP/LTP)的数据交付机制与排队模型,计算出更准确的重传回合数,构建了中继节点存储空间保管队列的平均长度模型。用该模型衡量节点存储空间的变化趋势,基于利克里德传输协议(LTP)数据块聚合的协议数据单元bundle数目与LTP数据段长度提出了联合优化方案。理论分析和仿真结果表明,在不影响数据正常传输的前提下,该优化方案可使节点存储空间的保管队列长度最短,即占用内存空间最小。在bundle的到达速率及信道误比特率发生变化时,优化后的队列长度分别减少了
Accurate measurement of the optical properties of biological tissue is very important for optical diagnosis and therapeutics. An artificial neural network (ANN)-based inverse reconstruction method is introduced to determine the optical properties of turbi
基于红外-可见光上转换材料进行防伪的可行性和可靠性的理论和实验分析,设计并研制了一套基于锁相放大技术的红外激光防伪识别系统。系统发射部分由恒压源、频率发生器和红外激光二极管等组成,将一定频率的电信号调制到激光二极管上,其中调制工作频率800 Hz,红外激光峰值波长975 nm;接收部分由滤光片、光敏管、前放滤波器、相敏检波器、低通滤波器和比较器等组成,完成红外到可见光转换后的检测,其中滤光片中心波长553 nm。实验证明所建立的系统对第5套人民币、新版英镑、新版越币、某高档烟酒等的识别是可行有效的。由于该
本文利用铁电晶体自发极化产生的强大周期性表面势,首次提出新的自由电子激光原理.据此原理,可以设计小型、廉价、高效率、高频率自由电子激光器,它在技术上是可能实现的.
美帝珀肯·埃耳默公司首次为光学加工应用特别设计了一种新型激光准直装置。公司讲，用这种低功率激光准直进行测量的精度比用通常的光学加工高5倍。除提高精确度外，这种激光准直装置还可由少数的不熟练的人员操作。