16×0.8nmSi基SiO2阵列波导光栅设计、制备及测试

叙述了一个完整的16通道硅基二氧化硅阵列波导光栅(AWG)的设计、制备及测试过程。通道间隔为0.8nm(100GHz),解复用器的插入损耗为16.8dB,其中材料损耗为11.95dB,相邻通道串扰小于-17dB,通道插损非均匀性小于2.2dB。     

16×0.8nm硅基二氧化硅阵列波导光栅设计

给出了更为合理的阵列波导光栅(AWG)的设计原则。在设计时兼顾了输出谱的非均匀性Lu和输出通道数N的要求,克服了设计中可能引起通道数N丢失和不考虑输出谱非均匀性Lu的缺点。用该方法设计了折射率差为0 75%和16×0 8nm的硅基二氧化硅AWG。采用广角有限差分束传播方法(FD BPM)对所设计的AWG进行了输出谱的模拟,得到了插损为 1.5dB、串扰为 48dB、通道非均匀性约为1dB的AWG,设计指标达到了商用要求。     

O波段8通道硅基二氧化硅平坦化阵列波导光栅的设计及制备

设计并制作了一款应用于IEEE 200/400GbE标准802.3bs的阵列波导光栅.该阵列波导光栅使用2.0%的超高折射率差硅基二氧化硅材料,使得芯片尺寸及损耗较小.为了获得平坦化的接收光谱,将输出波导进行展宽,采用多模波导结构,激发若干个高阶模,数个模式叠加使得原本高斯状的光谱顶部产生平坦化,形成箱形接收光谱.设计的阵列波导光栅的中心波长为1 291.10nm,通道间隔为800GHz,芯片尺寸为11mm×4mm.经过等离子增强化学气相沉积和感应耦合等离子刻蚀工艺制备了芯片,测试结果表明最小的插入损耗为-3.3dB,相邻通道间串扰小于-20dB,单通道1dB带宽在2.12~3.06nm范围,实现了良好的解复用和平坦化效果,在实际光通信系统中有一定的实用价值.     

阵列波导光栅解复用器输入/输出波导结构串扰的数值分析

本论文采用Marcatili方法分析矩形波导的模场特性,在此基础上计算了AWG波分复用/解复用器串扰与输入/输出波导间隙参数(dr/w),波导结构参数V的变化关系.计算了串扰值一定时,选取V参数与dr/w的关系曲线.分析了在不同折射率差波导中,串扰与偏振的相关性,为器件的整体优化设计提供了参考数据.     

650 nm聚合物阵列波导光栅波分复用器设计

选择在可见光波段具有较低吸收损耗的聚甲基丙烯酸甲酯-甲基丙烯酸环氧丙酯 共聚物作为波导包层材料,使用双酚A型环氧树脂作为折射率调节剂,根据材料的折射率设计了单模波导截面尺寸;然后,采用束传播法优化设计出16信道阵列波导光栅(AWG)器件的版图结构。利用Optiwave软件模拟了AWG器件的光传输特性,结果显示,器件的信道间隔为0.845 01 nm,插入损耗小于14 dB,串扰小于-25 dB。     

硅基二氧化硅阵列波导光栅制作工艺的研究

硅基二氧化硅阵列波导光栅是集成化波分复用光网络中的核心器件之一.对其制作工艺的研究对提高器件的性能具有重大意义.提出一种在波导上包层使用硼锗共掺高温退火的工艺方法,成功实现阵列波导间空隙的填充,并将阵列波导光栅的插入损耗成功降低约2 dB.相对于传统的硼磷硅玻璃工艺,此方法避免了剧毒气体磷烷的使用,工艺简便安全,同时降...     

阵列波导光栅设计原及优化

本文从波导光学和衍射光学理论出发，推导出阵列波导光栅（Arrayed-Waveguide Gratings）型波分复用器的重要结构参量；针对其性能参量，提出了一些优化设计方法。     

用Stigmatic Points法设计高性能80通道阵列波导光栅器件

采用Stigmatic Points方法改进传统的罗兰圆结构设计方法,给出一个实用化、高性能80通道阵列波导光栅器件设计方案.对采用这两种设计方法得到的器件性能结果进行了比较分析,指出了传统设计方法在设计大通道数阵列波导光栅器件中存在的问题以及Stigmatic Points方法对器件性能的改进.     

快速计算阵列波导光栅波导耦合系数的修正重叠积分方法

提出了一种修正的重叠积分方法用以计算阵列波导光栅(AWG)波分复用器件中光从自由传输区域到阵列波导的耦合系数,并和光束传播法(BPM)数值方法计算得到的结果做了比较通过比较分析,得出结论:当波导中心距不是太小时,用修正重叠积分这一快速方法是合适的.     

8-信道MMI阵列波导光栅复用/解复用器的研制

本文首先详细分析了基于自镜象效应的MMIDMUX器件的基本工作原理,在此基础上,在GaAs/GaAlAs系材料上完成了对8信道MMIDMUX的具体设计.该器件的输入、输出单模波导和SIE多模波导采用离散谱折射率法进行优化设计,最后获得了当输入、输出单模波导宽度为3μm、SIE多模波导宽度和长度分别为40μm和1731.45μm时,该器件对8信道波长的隔离度为～26dB,理论传输损耗为～0.24dB.     

基于绝缘体上的硅材料的全内反射型阵列波导光栅器件的设计

设计了一种基于绝缘体上的硅材料的全内反射型阵列波导光栅解复用器年。将一全内反射波导镜引入原弯曲的波导列阵中，该波导镜具有偏振补偿的功能和缩小器件尺寸的特点。在器年数值模拟的基础上，制作了原理性器件，并获得了初步的实验结果。     

光栅周期包含的Bragg层数对Bragg型凹面衍射光栅的影响

单个衍射光栅周期所包含的Bragg周期层数是连续Bragg齿型凹面衍射光栅的主要参数之一,该参数可改变光栅齿结构,对凹面衍射光栅的分辨力.自由光谱范围及衍射效率有重要影响.本文通过理论分析与仿真模拟,对比了4种不同层数的Bragg型凹面衍射光栅的特性参数.研究结果表明:在衍射光栅尺寸不变的情况下,改变单个光栅周期包含的Bragg周期层数不会显著提高器件主衍射级次的分辨力;单个光栅周期包含的Bragg周期层数与光栅可衍射的级次数成正相关.单周期层数的Bragg凹面衍射光栅的主衍射级次效率最高,其可衍射的级次数最少,且其他衍射级次分散的能量最少;增加单个光栅周期所包含的Bragg周期层数会降低主衍射级次的自由光谱范围.该研究对于设计低插损、高分辨率、宽工作波段的波分复用器或光栅光谱仪具有重要的指导意义.     

Design of Simple Wavelength or Polarization Filter/Combiner

We present an analytical and numerical analysis of a simple wavelength or polarization filter/combiner constructed from three single-mode rectangular waveguides. The device has the advantage of easy fabrication using existing planar light guide techniques and can be designed to discriminate between optical signals with distinct polarizations at a given wavelength or between signals at a fixed polarization with a wavelength separation of 9~nm or more. It is therefore well suited for CWDM metro-communication, local area network, sensor, or control applications.     

Impact of a Post-OTDM-Demultiplexing Optical Filter on Dense OOK OTDM-WDM Transmission

The impact of a post-OTDM-demultiplexing optical filter on the performance of dense on-off keying (OOK) optical time division multiplexing (OTDM)—wavelength division multiplexing (WDM) systems was studied. For return-to-zero (RZ) modulation, it was found that the additional filter working in a double-tier filter configuration did not offer any significant improvements to performance when the signal pulse width is optimized. Improvements generally increase only when the signal pulse width deviates from its optimal value and only for low spectral densities. For ideal non-return-to-zero (NRZ) modulation, however, significant improvements of around 1 dB are obtained using the double-tier configuration over a large range of spectral densities.     

Reduced back reflection design for an etched diffraction grating based planar demultiplexer

A design for a planar etched diffraction grating (EDG) demultiplexer is presented to reduce the back reflection. By reducing the diffracted field at the input waveguide, the present design makes the best effort to reduce the optical return loss. A design example is given to verify the performance. The spectral response at the input waveguide is simulated and the results show that at the wavelengths that cause back reflection, the reduced back reflection design only receives –47.7 dB of the input power, whereas the design without reduced back reflection receives –3.7 dB of the input power.     

Reconfigurable optical multiplexer based on liquid crystals for polymer optical fiber networks

In this work, different novel 3×1 multiplexer structures for being used in polymer optical fiber networks are proposed. Designs are compact, scalable, and of low consumption, capable of operating in a large wavelength range simultaneously 660, 850, and 1300 nm, due to the use of nematic liquid crystal cells. Light that comes from each input port is handled independently and eight operation modes are possible. Control electronics has been made using a programmable integrated circuit. Electronic system makes available the managing of the optical stage using a computer. An additional four optical sensors have been included for allowing the optical status checking. Finally, a polarization independent multiplexer has been implemented and tested. Insertion losses less than 4 dB and isolation better than 23 dB have been measured. In addition, 30-ms and 15-ms setup and rise times have been obtained. The proposed multiplexer can be used in any polymer optical fiber network, even in perfluorinated graded index one, and it can be specially useful in optical sensor networks, or in coarse wavelength division multiplexing networks.     

Performance analysis of optical WDM system based on unequal spaced channel allocation (USCA) scheme

Unequal spaced channel allocation (USCA) is a technique to reduce Four wave mixing (FWM). In this paper, system performance of 8 channel WDM system considering different optical transmitter formats (RZ, NRZ, Raised cosine and Gaussian) using USCA has been evaluated in terms of Q-factor. The simulation results reveal that four wave mixing is minimum for NRZ format. Also the effect of changing the laser power and increasing the bit rate has been observed.     

Transient Response and Control of Pump-Reflecting Raman Fiber Amplifiers

Abstract

This article analyzes the transient effect in pump-reflecting Raman fiber amplifiers. In order to better understand the impact of reflecting the unused pump power in the amplifier behavior, several scenarios are investigated. Results show that this pumping scheme has a worse response to dynamic channel add/drop. However, a pump-controlled gain-locked system is proposed that is able to mitigate the amplifier transient response. Following this approach, an efficient low-cost Raman fiber amplifier suitable for dynamic optical networks is obtained.     

A new synchronization scheme based on time division multiplexing and wavelength division multiplexing technology for practical quantum key distribution system

Three clock synchronization schemes for a quantum key distribution system are compared experimentally through the outdoor fibre and the interaction physical model of the the clock signal and the the quantum signal in the quantum key distribution system is analysed to propose a new synchronization scheme based on time division multiplexing and wavelength division multiplexing technology to reduce quantum bits error rates under some transmission rate conditions.The proposed synchronization scheme can not only completely eliminate noise photons from the bright background light of the the clock signal,but also suppress the fibre nonlinear crosstalk.     

高效异质结构四波长波分复用器的设计与优化

将两光子晶体单模波导平行、邻近放置构成一个光子晶体波导耦合结构.根据耦合和解耦合理论,设计了一种新型的高效异质结构四波长波分复用器.应用时域有限差分法模拟了该器件的效率,并通过改变一排介质柱的折射率,实现了较高的透射率.进一步发现在入射口处添加三对介质柱,可以有效地降低系统的反射,实现了四个波长的高效传输,四个波长的透射率均超过了90%.该器件不仅具有较高的透射率,而且其尺寸仅为36 μm×17 μm,在未来的光子集成回路中具有潜在的应用价值. 关键词： 光子晶体波导 耦合 异质结构 波分复用