共查询到19条相似文献,搜索用时 93 毫秒
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本文结合全反射理论和波导理论,分析传统的Y分叉全内反射高串音的原因,并得到了Y分叉TIR(Total Internal Reflection)光开关特征参数的近似解析表达式,提出了一种有效的改善全内反射光开关的方法,最后提出求解波导宽度W的计算过程,为全内反射光开关的设计提供了简明的理论分析方法。 相似文献
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采用新型聚合物材料Norland紫外固化胶(NOA)制备了聚合物M-Z型热光开关器件。对NOA薄膜材料的光学性质进行了表征,采用感应耦合等离子体(ICP)方法制备出形貌良好的波导器件。测得在1 550 nm波长下,长2.2 cm的直波导插入损耗为8.3 dB。在电极上施加直流信号,测得热光开关的消光比为11 dB,驱动功率为85 mW。引入直流偏置网络,获得了器件的开关特性曲线,测得开关器件的上升时间为1.085 ms,下降时间为489.5μs。实验结果表明:NOA材料在热光开关及其它聚合物光波导集成器件的制备中具有很大的应用潜力。 相似文献
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以二维三角晶格光子晶体为研究对象,在该光子晶体中引入两行以一行耦合介质柱为间距的平行单模线缺陷波导.通过分析和研究光子晶体波导耦合结构的耦合和解耦合特性,发现在不同频率下耦合波导的耦合长度不同.利用平面波展开法和定向耦合原理计算了在不同入射光频率下,缺陷波导间耦合波导的耦合长度,设计了一种新型超微光子晶体波导耦合型三波长功分器,实现了归一化频率分别为0.369、0.394、0.435的光波的分束效果.采用时域有限差分法验证了该功分器具有很好的功率分配效果.本文结果有助于光子晶体新型滤波器、定向耦合器、波分复用器、偏振光分束器以及光开关等光子器件的研究. 相似文献
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《中国光学与应用光学文摘》2006,(1)
TN2562006010418超紧凑型SOI基3×3MMI波导光开关的优化设计=Op-ti mal design of ultra-compact3×3SOI MMI optical swit-ches[刊,中]/贾晓玲(同济大学电子科学与技术系.上海(200092)),高凡…∥半导体光电.—2005,26(4).—294-298提出一种基于SOI材料的超紧凑型3×3MMI波导光开关,开关仅有一个多模波导,且多模波导采用更为紧凑的双曲结构。用FD-BPM方法对其各个状态进行了模拟和分析,并对器件的结构参数进行了优化设计。结果表明,这种光开关可以成功实现任意两输入和输出通道间的开关功能,优化后的开关呈现优良的综合性能,且整… 相似文献
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报道了对高斯型及指数型变耦合系数三波导耦合器的一些重要的全光开关特性进行的研究。利用四阶龙格一库塔方法对指数型和高斯型两类变耦合系数三波导耦合器进行了数值计算。数值计算结果表明:对于变耦合系数三波导耦合器而言,功率可在波导1与波导3之间100%转换,而波导2则不可能达到100%的功率输出。与双波导变耦合系数耦合器相比,在相同的最大耦合系数情况下三波导变耦合系数耦合器开关曲线要更陡一些.即具有更好的开关特性。与平行三波导耦合器相比,变耦合系数三波导耦合器作为光开关的最大优点在于开关曲线中不存在振荡。 相似文献
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光子晶体异质结耦合波导光开关 总被引:2,自引:0,他引:2
以二维三角晶格光子晶体为研究对象,在该光子晶体中引入两行平行的单模线缺陷波导,以一行耦合介质柱为间距,通过调节部分耦合介质柱的折射率,构筑了光子晶体异质结耦合波导光开关结构。利用平面波展开法和定向耦合原理计算了在不同入射光频率下,缺陷波导间耦合介质柱的折射率不同时的耦合长度,确定了合适的光子晶体异质结耦合波导光开关的结构参数。利用时域有限差分法研究了该光开关中耦合介质柱的折射率变化及异质结构介质柱的位置分布对光信号输出路径的影响。结果表明,通过改变该结构中耦合介质柱的折射率可以改变光的输出路径,可实现光的开关行为。并且异质结构介质柱位置的随机分布对该光开关的影响不大,有助于光子晶体新型滤波器、定向耦合器、波分复用器以及光开关等光子器件的研究。 相似文献
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利用金属表面等离激元(SPP)对光波的束缚和局域增强作用,设计了一种基于金属-电介质-金属波导布拉格光栅的全光开关。根据波导的电介质材料及其结构对有效折射率的调制作用,确定了开关各结构组成部分的材料和尺寸。通过引入金属波导滤波结构对抽运光和信号光进行了有效地分离,防止了抽运光对信号光及后续光路的干扰。使用时域有限差分算法(FDTD)对开关性能进行仿真,结果表明:新设计的全光开关在抽运光的光强为50 MW/cm2时其消光比达到7.32 d B,开关响应时间小于2 ps,结构的横向尺寸约为400 nm。 相似文献
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Optical switches play an important role in all optical communication networks and multiprocessor computer systems. The 2×2 and 4×4 optical switches are the basic units of large-scale switch matrices. Using a conventional polarization control method, the optical switch system and structure is optimized, and a novel optical switch is proposed, which has the advantages of relatively low crosstalk and insertion loss, compact and simple construction, higher performance and cost effectiveness. First, a novel 2×2 optical switch is proposed using phase spatial light modulator (PSLM), polarizing beam splitter (PBS) and mirror. This configuration uses fewer optical components, is compact in structure, efficient in performance, and insensitive to polarization of the signal beam. Second, a new optical experimental module of 4×4 optical switch is presented by cascading a 2×2 optical switch. The routing method of polarization-independent bidirectional 4×4 optical switch is investigated. Finally, the operational characteristics of the polarization-independent bidirectional 2×2 and 4×2 optical switches are discussed in detail. 相似文献
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A.M.C. Dawes D.J. Gauthier S. Schumacher N.H. Kwong R. Binder A.L. Smirl 《Laser \u0026amp; Photonics Reviews》2010,4(2):221-243
We review recent theoretical and experimental efforts toward developing an all‐optical switch based on transverse optical patterns. Transverse optical patterns are formed when counterpropagating laser beams interact with a nonlinear medium. A perturbation, in the form of a weak switch beam injected into the nonlinear medium, controls the orientation of the generated patterns. Each state of the pattern orientation is associated with a state of the switch. That is, information is stored in the orientation state. A realization of this switch using a warm rubidium vapor shows that it can be actuated by as few as 600 ± 40 photons with a response time of 5 µs. Models of nonlinear optical interactions in semiconductor quantum wells and microresonators suggest these systems are also suitable for use as fast all‐optical switches using this same conceptual design, albeit at higher switching powers. 相似文献
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光突发交换的交换控制策略和光缓存配置 总被引:4,自引:2,他引:2
光突发交换是面向下一代互联网的光交换模式.讨论了异步光突发交换系统的交换控制策略以及相应光缓存的优化配置策略.除了传统预约模式的交换策略,还研究了非预约和改进型预约模式,它们的性能评估由计算机仿真给出.结果表明:在条件相当情况下,改进型预约模式具有最低的丢包率.同时光缓存的配置对上述几类交换控制策略的性能都有很大影响,仿真结果指出:光缓存的粒度对系统性能具有重要影响,所讨论的几类交换模式都存在最佳时延粒度,研究结果对光交换矩阵的设计有指导意义. 相似文献
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A theoretical design of a defect ring optical waveguide network is proposed to construct a pump‐free ultrahigh efficiency all‐optical switch. This switch creates ultrastrong photonic localization and causes the nonlinear dielectric in the defect waveguide to intensely respond. At its ON state, this material defect without Kerr response helps to produce a pair of sharp pass bands in the transmission spectrum to form the dual channel of the all‐optical switch. When it is switched to its OFF state, the strong Kerr response induced refractive index change in the high nonlinear defect waveguide strongly alters the spectrum, leading to a collapse of the dual channels. Network equation and generalized eigenfunction method are used to numerically calculate the optical properties of the switch and obtain a threshold control energy of about 2.90 zJ, which is eight orders of magnitude lower than previously reported. The switching efficiency/transmission ratio exceeds 3× 1011, which is six orders of magnitude larger than previously reported. The state transition time is nearly 108 fs, which is approximately two orders of magnitude faster than the previously reported shortest time. Furthermore, the switch size can be much smaller than 2.6 µm and will be suitable for integration. 相似文献
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利用成熟的偏振控制技术,设计了一种由偏振光分束器、相位型空间光调制器和反射镜构成的2×2光开关,该光开关所用器件少,具有结构简单紧凑、控制灵活方便、功能实现与信号光的偏振态无关以及可以双向交换等特点;在此基础上通过2×2光开关的串连,设计了一种与偏振无关的双向4×4光开关的实验模块,根据其路由选择与控制方法,得到了4×4光开关实现信号光全排列无阻塞输出与交换对应的路由状态表,并对该实验模块的功能实现进行了详细的分析与讨论。 相似文献
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4×4自由空间光开关结构及其矩阵分析 总被引:10,自引:5,他引:5
光开关是全光通信网络中的一种重要的光无源器件。提出了一种4×4自由空间光开关的结构设计方法,并进行了矩阵理论分析。该4×4光开关具有新颖的光模块化结构,该光开关结构仅由偏振分束组合棱镜,λ/4波片,λ/2波片,直角棱镜,全反镜和偏振光调制器组成,对光开关的控制与输入光束的偏振态无关。所有的输出端口可以和输入端口无阻塞地互连交换。这种新型的光开关结构具有光学元件少,结构紧凑,模块化,与偏振无关的特点。基于4×4光开关的矩阵分析得到了路由控制表,为4×4光开关从任意输人端口到任意输出端口的路由控制状态提供了理论分析手段,从而可以方便地实现无阻塞地光交换开关矩阵的路由控制功能。 相似文献
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Sisir Kumar Garai 《Optics & Laser Technology》2011,43(1):124-131
Optical data comparator is the part and parcel of arithmetic and logical unit of any optical data processor and it is working as a building block in a larger optical circuit, as an optical switch in all optical header processing and optical packet switching based all optical telecommunications system. In this article the author proposes a method of developing an all optical single bit comparator unit and subsequently extending the proposal to develop a n-bit comparator exploiting the nonlinear rotation of the state of polarization of the probe beam in semiconductor optical amplifier (SOA). Here the dataset to be compared are taken in frequency encoded/decoded form throughout the communication. The major advantages of frequency encoding over all other conventional techniques are that as the frequency of any signal is fundamental one so it can preserve its identity throughout the communication of optical signal and minimizes the probability of bit error problem. For frequency routing purpose optical add/drop multiplexer (ADM) is used which not only route the pump beams properly but also to amplify the pump beams efficiently. Switching speed of ‘MZI-SOA switch’ as well as SOA based switches are very fast with good on–off contrast ratio and as a result it is possible to obtain very fast action of optical data comparator. 相似文献
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Design of Two-Dimensional Optimized Banyan Networks 总被引:2,自引:0,他引:2
A smart two-dimensional optical Banyan network is proposed. Polarization switching logic of light is applied for the design of this network. The main element for the connections of the network is an optical crossbar switch that is composed of a half-wave plate, a programmable polarization switch, and a couple of birefringent plates. By the proposed optical crossbar switches, all permutations of the link patterns required in the network are generated due to the optimized design of the switching logic. As a result, complicated routing control of ordinary Banyan networks is much reduced and a simple two-dimensional optical Banyan network with straight interconnections between successive stages of the networks can be realized. 相似文献