基于双环形谐振腔结构的二维光子晶体波分复用器

为了实现光波的波分复用功能并且提高光波的辐射效率,设计了一种基于双环形谐振腔结构的二维光子晶体波分复用器.首先,对光子晶体结构参数进行设计,通过谐振腔和微腔耦合选择不同频率的光波,设计光子晶体滤波器模型;然后,根据模式耦合理论确定主干波导与谐振腔之间的最佳耦合条件,设计波分复用器;最后,加入散射介质柱并调整两谐振腔之间...     

二维平板光子晶体微腔与波导的耦合北大核心CSCD

光子晶体是介质介电常数呈周期性排布的结构,具有光子带隙,处于光子带隙中的电磁波无法在其中传播。二维平板光子晶体是通过在衬底上刻蚀周期性排列的空气孔柱而形成的结构,由于其具有优良的控制光传播的特性而得到广泛的研究和应用。介绍了在二维平板光子晶体中引入缺陷形成的光子晶体微腔和波导的方法和性质。通过调整几何参数控制微腔与波导之间的耦合,实现基于二维平板光子晶体的全光开关、光存储、单光子源等光学器件并讨论其在量子光学网络中的应用。     

二维光子晶体波导和微腔缺陷态研究

利用二维三角晶格及正方晶格介质柱光子晶体TE偏振的禁带与介质柱半径的变化关系,分析了二维光子晶体缺陷态的分布.根据光子晶体波导间的耦合作用,计算其耦合长度设计合理的定向耦合器.通过分析波导与微腔的耦合特性,选取不同的传输方向,可以设计多种基于光子晶体波导与微腔耦合的波分复用系统.     

光子晶体共振耦合波分复用器的设计与研究

设计了一种由光子晶体环形腔与微腔组成的组合腔滤波器,在环形谐振腔中增加两个散射介质柱,环形腔和波导之间相隔一排介质柱,输出波导与输入波导呈垂直关系,形成一种新的环形腔。通过环形腔、微腔及波导的共振耦合,设计了一种能高效率输出的波分复用/解复用器。     

含缺陷光子晶体波分复用器研究

利用光子晶体的光子禁带和体积小的优点,在光子晶体中适当设计线缺陷和点缺陷,使这些缺陷会形成波导和微腔.根据耦合模理论,波导与波导及波导与微腔之间会发生耦合现象,通过调节耦合长度和微腔中心半径的大小,可以选择不同波长的光波在各信道中通过.依此原理,可以制作相应的光子晶体波分复用器.     

用于波分复用的光子晶体滤波器

本文从光子晶体的光子频率禁带特性出发，提出了用2个或以上的均匀周期结构光子晶体叠加在一起，形成叠层结构光子晶体，以获得窄带滤波特性的设想；利用光学传输矩阵法对这种结构进行了数值计算，结果证实了构思的正确性；设计了信道间隔为8nm的8信道波分复用（WDM）和信道间隔0.8nm的8信道密集波分复用（DWDM）光子晶体滤波器。     

光子晶体微腔发光二极管

光子晶体微腔因其具有增强自发辐射、定向输出和单模工作的能力而受到广泛关注。介绍了光子晶体微腔发光二极管的基本原理、设计、特性、制作及其典型器件。     

光子晶体波导定向耦合功分器的设计

将相互耦合的3平行光子晶体单模波导看成一个多模干涉系统,通过研究二维正方晶格光子晶体波导多模干涉的自映像效应,优化设计了一种新型1×2光子晶体波导定向耦合分束器,采用时域有限差分法对其传输特性进行模拟分析。设计过程中,根据多模干涉耦合区中周期出现的双重像的位置确定两个单模输出波导的位置,通过改变输出波导和耦合区连结的一个介质柱位置构成波导微腔结构,改变耦合区中的模场分布,实现模式匹配,从而明显减小分束器的反射损耗。计算结果表明,移动介质柱距离输出单模波导和多模波导连结处1.85a位置处时,对于波长为1.55μm的入射光,该分束器的透射率可高达99.04%。     

Determining the maximum signal power in 10 Gbit/s WDM optical networks

Nowadays in optical networks there is a trend line to extend the maximum transmission distance. Several techniques are known; however, the simplest one is to increase the signal power in the optical fiber. The task of minimizing the number of inline amplifiers in order to increase the deployed system’s cost effectiveness leads to increasing the signal power. The only problem is the nonlinear behavior of the optical fiber which limits the signal power to be inserted into the optical fibers. In this paper, we present a model to calculate analytically the signal quality deterioration due to nonlinear effects at the receiver point. As a result, we give the exact value of the optimal signal power at the transmitter point or at the output of the inline amplifiers for 10 Gbit/s wavelength division multiplexed (WDM) systems.

光子晶体及二维光子晶体波导

光子晶体是一种新兴的光学材料,其各种优异的光学特性可以用来制作所需要的光子晶体器件,。本文介绍了一维、二维、三维光子晶体的结构、特性及其主要的理论研究方法、实验制备方法,并着重阐述了二维光子晶体波导的特性及其制备方法及国内外研究进展。     

波分复用光网络的自愈方法分析

WDM (WavelengthDivisionMultiplexing ,波分复用 )系统的应用使得大容量的业务日益集中于同一系统内 ,这同时提高了对网络自愈性能的要求 ,从而导致各种自愈技术的发展。因为光器件具有高速交换的优点 ,因而从光层对业务恢复具有极大的优越性。文中主要分析了几种典型的光层的自愈方法     

光子集成技术在波分多路系统的应用

本文介绍光子学的一种新趋向，即光子集成（ＰＩＣ）技术在波分多路（ＷＤＭ）光纤通信系统应用的初步尝试。在说明ＷＤＭ系统在高速光纤通信网的重要性和ＰＩＣ技术在ＷＤＭ系统应用的必要性之后，本文列举Ｂｅｌｌｃａｒｅ最近研制ＰＩＣ／ＷＤＭ取得初步成功的两个例子：一是多路光载波的ＭＱＷ／ＤＦＢ激光管阵列，用于ＷＤＭ发送机；二是ＩｎＰ平面反射光栅合波／分波器，有助于ＷＤＭ网中各种功能器件的集成。     

Optimal Higher-order Dispersion Management Methods in WDM Transmission Systems

In order to reduce the four-wave mixing crosstalk and avoid the signal waveform distortion in long-haul dense-wavelength division multiplexing systems, helpful methods on how to choose suitable local parameters in higher-order dispersion managed line are presented, which are used to increase the system capacity and improve the system performances.     

WDM＋TDM40Gbit／S技术的应用前景探讨

从WDM＋TDM40Gbit/s所遇到的技术难题着手，从各个角度分析并提出技术解决方法，最后探讨其在今后的应用前景。     

Design methodology for WDM backbone networks using FWM-aware heuristic algorithm

The problem of lightpath topology design (LTD) and traffic routing over the lightpaths for wavelength-routed optical backbone networks has been investigated extensively in the past using heuristic as well as linear-programming based approaches. Sensitivity of such long-haul backbones to physical-layer impairments is required to be adequately addressed during LTD phase to improve overall performance. For optical communication using wavelength-division multiplexing (WDM) over a long-haul fiber backbone, four-wave mixing (FWM) may become one of the significant transmission impairments. Intrinsically, for a WDM-based wavelength-routed network with wavelengths assigned using equally-spaced channels, the generated FWM components are found to remain more crowded at the center of the fiber transmission window. Using this observation, we propose an LTD scheme employing a unique wavelength assignment (WA) technique, wherein long lightpaths (traversing through a larger number of fiber links) are allocated wavelengths at the either edges of the fiber transmission window whereas short lightpaths (consisting of fewer fiber links) are placed in the middle of the transmission window, thereby reducing the FWM crosstalk for long lightpaths. Since long lightpaths comprise of large numbers of fiber links and intermediate nodes, they experience large amplified spontaneous emission (ASE) noise and switch crosstalk. Therefore, by using the proposed WA technique, long lightpaths while suffering from more ASE noise and switch crosstalk get subjected to lesser FWM crosstalk leading to a more uniform distribution of overall optical signal-to-noise ratio for all the lightpaths across the network. Analysis of our results indicates that the proposed FWM-aware LTD scheme with the novel WA technique can achieve similar congestion levels (of lightpaths) and bandwidth utilization efficiency without any need of additional network resources as compared with the existing FWM-unaware LTD schemes.     

Design alternatives for <Emphasis Type="Italic">N</Emphasis>-stage WDM optical planar permutation networks

Planar permutation networks are a class of multistage switching networks with no crossover between paths that interconnect switching elements. A well-known class of planar networks is the N−Stage network that provides a good compromise between the crossbar and the Benes network. In this paper, we address the problem of designing cost-effective N-Stage optical planar networks with space-wavelength switching capability. Such networks are used for switching in communication and computing systems that employ Wavelength Division Multiplexing (WDM) technology. We investigate two classes of space-wavelength N-stage planar networks, and for each class, we design a number of switching networks and analyze their hardware complexity. In addition, we propose a new method for designing a class of space-wavelength planar networks with reduced complexity. It is shown that, for F ≤  W (where F is the total number of fibers and W that of wavelengths) the proposed method results in planar networks with an average of 67% reduction in overall cost compared to that of networks based on fixed-range wavelength converters.