减少聚合物阵列波导光栅损耗的蒸气回溶技术

阵列波导光栅(AWG)器件是波分复用(WDM)系统的一种关键器件,其中,聚合物阵列波导光栅由于其制备工艺、器件集成等方面的优势而受到人们的日益关注。侧壁散射损耗是聚合物阵列波导光栅损耗的一个主要因素,减少阵列波导光栅波导的侧壁损耗对制备低损耗阵列波导光栅具有重要意义。一种蒸气回溶技术被用来有效地减少硅基聚合物阵列波导光栅的散射损耗,该技术的机理是饱和溶剂分子融入并软化波导侧壁,增加其流动性,从而降低波导侧壁粗糙度。用扫描电镜方法验证了用该技术能获得更光滑的波导侧壁。对直波导和阵列波导光栅样品进行回溶处理,测试后得到直波导的侧壁散射损耗减少2.1 dB/cm,阵列波导光栅中心信道和周边信道的插入损耗分别减少5.5 dB和6.7 dB,串扰减少2.5 dB。     

聚合物微环谐振波分复用器传输特性的理论分析

根据耦合模理论,给出了1×N信道微环谐振波分复用器(MRRWM)的光强传递函数通用公式,并分析了微环谐振波分复用器的传输特性。利用参量优化结果,在中心工作波长约为 1.55μm、波长间隔约 5.6 nm的情况下,对1×8信道硅基聚合物微环谐振波分复用器进行了数值模拟。计算结果表明,该器件具有以下优良的性能:分波光谱准确,自由光谱区约为18 nm,对于半径10μm以上的微环弯曲损耗很小,且器件的插入损耗主要由波导的传输损耗决定,振幅耦合比率为0.2时对应的每条竖直输出信道的插入损耗在0.57 dB以下,信道间的串扰小于-18.5 dB,输出谐振峰3 dB带宽可达0.25 nm,最小背景光的强度约为3.8×10-4。     

一种有效提高薄膜滤光片型密集波分复用器器件性能的方法及其实验研究

对光梳状滤波器加薄膜滤光片型模块制作密集波分复用器(DWDM)的两种应用方案进行了研究,提出了一种提高插损一致性、信道隔离度及减小串扰的结构方案。对新结构方案与常规结构方案进行了理论分析及实验研究,结果表明新结构可将级联次级峰由大于-30dB降至-50dB以下。用16波50GHz的密集波分复用器件拼接进行的实验表明最终器件的插损减小0．869dB,插损一致性减小2．005dB,相邻信道隔离度提高1．004dB,非相邻信道隔离度提高42．903dB．总串扰提高1．68dB。该方案不仅可以应用到光梳状滤波器与薄膜滤光片型模块拼接高性能的超密集波分复用器件．同样也可适用于阵列波导光栅等类型的密集波分复用器件中以降低工艺难度,提高性能指标。     

一种通带平坦的粗波分复用/解复用器件的研制

随着粗波分复用(CWDM)系统在城域网和接入网中日益广泛的应用,人们对粗波分复用／解复用器的研究也逐渐展开。报道了一种8通道波长间隔为20nm的粗复用／解复用器。该器件基于阵列波导光栅(AWG)原理设计,利用平面光波导技术(PLC)制作,采用多模干涉输入结构和“S”形阵列波导结构,实现了较宽的通带宽度和较低的串扰。实验测得1dB带宽大于10nm,相邻串扰大于24dB,非相邻串扰大于32dB。介绍了其设计原理和制作过程,给出了光束传播法(BPM)数值模拟结果,并和实验结果进行了对比。     

波长选择性平行耦合微环谐振四端口光路由

利用四个平行耦合单环谐振器作为基本路由单元,数值模拟了一种可路由三种信道波长的四端口光路由器.为了实现单模传输、低传输损耗以及微环波导和信道波导的相位匹配,优化了基本路由单元的结构参量.给出了路由器的器件架构和设计方法,计算了链路光谱、插入损耗、串扰等路由特性.在选定的三个信道波长(1550、1551.6、1553.2 nm)下,器件沿不同路径的插入损耗范围为0.02～0.6 dB,器件串扰的范围为-23.41～-37.71 dB.与具有相同波导参量的基于交叉耦合双环谐振器的四端口光路由器相比,该四端口光路由器在串扰和波长选择性方面略显不足,但其使用的微环数量由8个降低为4个,插入损耗由1.62 dB降低为0.02 dB.     

微机械FP腔可调谐滤波器在WDM系统中的串扰分析

介绍了一种以FP谐振腔为基础,用于波分复用系统的MOEMS器件-电控可调谐FP光滤波器.器件采用微电子机械加工技术研制.研究了FP型解复用器在密集波分复用系统中引入的信道间串扰对系统的影响,并分别讨论了激光器线宽、滤波器带宽、信道间距对串扰的影响.在信道间隔为100GHz,激光器线宽为5GHz,串扰可达到-21dB左右.     

波长选择性平行耦合微环谐振四端口光路由（英文）

利用四个平行耦合单环谐振器作为基本路由单元,数值模拟了一种可路由三种信道波长的四端口光路由器.为了实现单模传输、低传输损耗以及微环波导和信道波导的相位匹配,优化了基本路由单元的结构参量.给出了路由器的器件架构和设计方法,计算了链路光谱、插入损耗、串扰等路由特性.在选定的三个信道波长(1 550、1 551.6、1 553.2nm)下,器件沿不同路径的插入损耗范围为0.02~0.6dB,器件串扰的范围为-23.41~-37.71dB.与具有相同波导参量的基于交叉耦合双环谐振器的四端口光路由器相比,该四端口光路由器在串扰和波长选择性方面略显不足,但其使用的微环数量由8个降低为4个,插入损耗由1.62dB降低为0.02dB.     

基于锥形渐变不对称耦合的模式复用/解复用器

设计了一种采用锥形渐变不对称耦合结构的模式复用/解复用器,并利用商用的0.18μm互补金属氧化物半导体兼容工艺进行制备.通过控制锥形波导的宽度,基于模式有效折射率匹配原则,实现锥形波导中的基模与多模波导中的高阶模式相互转化.测试结果表明:当器件用于TE0、TE1和TE2三个模式复用与解复用时,在1 530nm到1 570nm波长范围内,串扰低于-8.05dB;而当器件复用与解复用TE0和TE2时,串扰低于-16.43dB.     

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。     

阵列波导光栅解调系统光电集成中Si纳米线AWG的设计

设计了一种阵列波导光栅解调集成系统中的8通道Si纳米线阵列波导光栅波分复用器。根据材料的折射率设计了单模波导截面尺寸,利用光束传播法对所设计阵列波导光栅进行了模拟。结果表明,器件尺寸为200μm×219μm,远小于目前技术较成熟的硅基SiO2的尺寸,光功率分布符合高斯分布,信道间隔为1.8nm,串扰小于-21dB。对小尺寸AWG的设计具有参考意义。     

两点法设计平场型EDG波分复用器件

利用两点法(two stigmatic points method)对平场型蚀刻衍射光栅(EDG)波分复用器件进行了优化设计.与传统EDG相比,该方法以较小的性能损失为代价,极大简化了制作工艺.通过标量波动衍射理论对16通道的该型器件进行了数值模拟,结果表明:在用光探测器陈列接收的情况下,额外的功率损耗约为1dB,信道间的不均匀性小于0.3dB,串绕小于-30dB.     

Etched-Diffraction-Grating-Based Planar Waveguide Demultiplexer on Silicon-on-Insulator

An optical wavelength demultiplexer with the etched diffraction grating (EDG) on the silicon-on-insulator (SOI) material is demonstrated. Fabricated by the wet-anisotropic-etching method, 90° turning mirrors are used to bend waveguides, and the size of the EDG-based demultiplexer is minimized to only 16×2.5 mm². The crosstalk is below −16 dB. The on-chip loss is about 9.97 dB, which is composed of about 8.72 dB excess loss and 1.25 dB diffraction loss. The polarization-dependent central wavelength shift is below 0.13 nm, and the polarization-dependent loss is about 0.35 dB. The sources of the crosstalk and loss are discussed in details, and the related measures to improve the performance are also presented.     

基于光纤光栅的波长可调谐光分插复用器

本文报道了一种基于光纤光栅的波长可调谐光分插复用器.可连续线性调谐5.3nm来选择不同的信道进行上下载信息.用宽带光源对该器件的性能进行了测试;用该器件在4波长全光纤激光器作信号源的光纤通信传输实验系统中做了解复用实验.实验表明该器件能很好地下载光信号,相邻信道隔离度达到29dB,具有一定的应用价值.     

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.     

Design and fabrication of arrayed waveguide grating using fluoropolymer PFS-co-GMA

A 33×33 polymer arrayed waveguide grating (AWG) multiplexer is optimized and fabricated. This device is made of polymeric materials named 2,3,4,5,6-pentafluorostyrene-co-glycidylmethacrylate (PFS-co-GMA). The central wavelength and wavelength spacing are designed to be 1550.918 and 0.8 nm, respectively. The calculated results are: the 3-dB bandwidth is about 0.24 nm, insertion loss is about 8.4 dB and crosstalk is −33.7 dB. The corresponding measured results are: the center wavelength is about 1550.85 nm, wavelength channel spacing is about 0.81 nm, 3-dB bandwidth is about 0.35 nm, crosstalk is about −20 dB, insertion loss is between 10.4 dB for the central port and 11.9 dB for the edge ports.     

Characteristic Analysis of a Smooth Square Microring Resonant Wavelength Multiplexer

Novel formulas of amplitude coupling ratio and transmission functions are presented for a smooth square microring resonant (MRR) wavelength multiplexer. By using these formulas, transmission characteristics are analyzed and some parameters are optimized for such a 1 × 8 polymeric device around the central wavelength of 1550.92 nm with the wavelength spacing of 1.6 nm. In the design of the device, by using the smooth squares, a thicker coupling layer is obtained, and by resonating the light at different resonant orders in different filter elements, the ring radius increment is increased sufficiently, which is of benefit to the fabrication of the device. When the amplitude coupling ratio is 0.2, the 3-dB bandwidth of the spectral response is about 0.2 nm; the ratio between -1 dB and -10 dB bandwidths is about 0.2; the insertion loss is less than 1.33 dB; and the crosstalk is below -21 dB for every vertical output channel of the device.     

Integrated all-optical nonlinear device for re- configurable add/drop and wavelength shifting of WDM signals

A novel configuration is proposed for an all-optical device performing two key functionalities in a communication network based on wavelength-division-multiplexing (WDM): reconfigurable add/drop and wavelength shifting of single channels. The device is based on guided second-order nonlinear interactions, such as sum-frequency generation and difference-frequency generation, between the WDM channels and a suitable pump beam. A directional coupler and two parallel waveguides allow the spatial separation between the main WDM signal and the dropped or wavelength-shifted channel for a subsequent routing in the desired path. A first numerical simulation provided a cross-talk level in the dropped channel lower than -41 dB and a wavelength-shifting range of more than 40 nm. Received: 18 May 2001 / Published online: 30 October 2001     

Analysis of a 1×32 polymer microring resonant wavelength de-multi/multiplexer assistant with interleave filter

A new 1×32 wavelength de-multi/multiplexer utilizing the microring resonator and interleave filter is proposed in this paper. A novel formula of transfer functions is presented, the parameters of microring are optimized, and the transmission characteristics of the system are analyzed. The channel spacing of the presented device is 0.4 nm. The analytical result shows that the crosstalk between adjacent channels can be reduced greatly and the filter response of the device can be improved by using the interleave filter. A bandwidth (3 dB) of 0.21 nm, an insertion loss less than 1.1 dB, and crosstalk below −32 dB were obtained for the optimized device. A method for compensating the manufacturing tolerances is discussed.