Parallel-stage-based reconfigurable optical add-drop multiplexer for WDM optical transport networks

This letter proposes a simple and flexible reconfigurable optical add-drop multiplexer (ROADM) based on parallel-stage configuration using Mach-Zehnder-based fiber gratings, 1/spl times/2 optical switches, and Y-model combiners. The proposed ROADM with four-stage parallel configuration is designed and experimentally investigated to show its performance in full wavelength selection and advantages in reducing the discrepancy of the insertion loss between channels and upgrading.     

Design and fabrication of low-loss polymer waveguide components for on-chip optical interconnection

This paper reports the fabrication and characterization of straight and curved polyimide waveguides for on-chip optical signal distribution in GaAs-based optoelectronic integrated circuits. Polyimide ridge waveguides with propagation losses (at 830 nm) as low as 0.6 dB/cm have been fabricated. S-bends and splitters with low curvature losses and good splitting ratios have also been successfully fabricated and tested. The effects of the material properties and radius of curvature on the optical losses are presented, and the advantages of this polymer technology are discussed.     

OTDM add-drop multiplexer based on time-frequency signal processing

A time-division add-drop multiplexer capable of high-extinction-ratio operation is presented both theoretically and experimentally. The approach used is based on time-to-frequency domain conversion of optical signals and relies upon the switching of linearly chirped optical pulses. By converting a 40-Gb/s optical time-division multiplexing (OTDM) signal to 4 /spl times/ 10-Gb/s wavelength-division multiplexing (WDM) channels and using fiber Bragg gratings for frequency-domain add-drop multiplexing, a timeslot suppression ratio in excess of 30 dB and error-free operation for the dropped, through, and added channels were achieved. A further stage of WDM-to-TDM signal conversion was used to map the resulting signal back into the time domain. Moreover, it is shown that it is straightforward to simultaneously operate on multiple channels by simply cascading gratings to make more complex filtering functions without the requirement for any further synchronization of the tributary channels.     

空间级联可调谐光滤波器方式实现光分插复用器

提出一种采用空间级联可调谐光滤波器方式实现的OADM.该器件不但具有集成度高、体积小、插入损耗低、信道间插入损耗差异小的特点,而且能够在控制电路的作用下灵活选择上下路波长及其数量,为构建灵活、高性能的WDM网络提供了选择.     

低损耗聚合物互连光波导的制备及性能测试

对应用于宽带光互连的光印刷电路板(OPCB)制备技术进行了研究。作为光互连系统的传输介质,我们研究了互连光波导的性能。基于紫外光刻技术,在常规PCB基底上制备了聚合物光波导,研究了光波导的制备流程以及工艺参数;并且通过不断优化工艺参数,制备得到了低损耗的光波导;通过测试光波导的传输损耗以及眼图,分析了光波导的性能。光波导在850nm波长条件下的传输损耗可以达到0.13dB/cm,实现了10Gbit/s光通信信号的传输。     

Integrated laser and add-drop optical multiplexer for narrowband wavelength division multiplexing

The fabrication and characterisation of a monolithically integrated narrowband add-drop multiplexer and DBR laser are reported. Multiplexer bandwidth of 2-3.5 nm have been measured with a Bragg extinction ratio >23 dB.<>     

一种基于MZI的聚合物光波导加速度计

提出了一种基于马赫增德尔干涉仪（MZI）的聚合物光学波导加速度计。理论推导了MZI结构的传输函数,仿真分析了悬臂梁结构参数与器件灵敏度的关系,制备和测试了基于聚合物材料和柔性衬底的加速度传感芯片。制备得到了4 μm×4 μm单模传输芯层波导的传感芯片。搭建了集成光学加速度测试系统,采用比较校准法对探测器输出电压信号进行标定,实现了传感芯片因施加加速度后输出光强变化的测试,完成了加速度测量。该加速度传感芯片分辨率为10-2 g,动态范围为±2 g。     

光电印制电路板用聚合物光波导材料研究进展及应用

随着PCB对高密度和高速率传导的要求越来越高,光电印制电路板(EOPCB)作为PCB的新一代产业已成为历史发展的必然。无论从材料的结构、性能,还是材料自身的成本和可加工性,聚合物光学材料都显示出了比无机材料更加优越的应用前景。对聚合物光波导材料的研究主要集中在提高其热及化学稳定性和降低材料的吸收损耗等方面。本文首先对光电印制电路板进行了简要概述,接着对聚合物光波导的分类、特点、材料、主要性能及提高方法分别作了比较详细介绍,然后对几种常用的聚合物光波导材料的单体及合成作了进一步阐述,最后对聚合物光波导加工成型工艺和相关性能检测方法进行了详尽阐述。     

Ultra low-loss 1 X 2 multiplexer using thin-film filters on polymer integration platform

Compact 1 X 2 wavelength multiplexer modules employing thin-film filters integrated into polymer planar waveguide circuits are presented. The modules also feature on-chip deep-etched U-grooves for precise fibre-chip coupling. Insertion loss <1 dB, crosstalk <-30 dB, and return loss <-50 dB have been achieved by various technological optimisations.     

OTDM add-drop multiplexer based on XPM-induced wavelength shifting in highly nonlinear fiber

In this paper, we study experimentally and numerically simultaneous time-domain add-drop multiplexing for high-speed optical time-division multiplexing (OTDM) networks based on cross-phase-modulation (XPM)-induced wavelength shifting in a 50-m highly nonlinear fiber. This scheme needs only a single-channel clock rate and does not alter the input signal wavelength. Simultaneous add and drop operations at 80 Gb/s have been demonstrated experimentally with less than 1-dB power penalty for the dropped channel and no distinct bit-error-rate (BER) degradation for the added channel. Numerical simulations show that the experimental results are only limited by the available signal pulsewidth, and simultaneous add-drop multiplexing at 160-Gb/s or higher bit rates is possible with this scheme by employing control and signal pulses with proper pulsewidths.     

硅基光波导材料的研究

光波导是集成光路及其元器件中最基本的构成单元。本文介绍了各种不同类型的光波导材料的特性。硅材料作为目前研究得最透彻的半导体材料,它在光电子领域的应用也是令人关注的。硅基光波导材料种类繁多,主要包括聚合物、外延硅/重掺杂硅、SiO₂,SOI和SiGe/Si等。硅基光波导材料是实现硅基光波导器件的基础,本文阐明了它们各自的特点和应用前景。其中聚合物、SiO₂和SOI波导是目前研究的热点。     

Integrated optical waveguide polarizer based on photobleaching-induced birefringence in an electrooptic polymer

A TE-pass waveguide polarizer is fabricated by utilizing the photobleaching-induced birefringence at room temperature in an electrooptic polymer. The polarizer consists of the photobleached waveguide supporting only TE mode, which is integrated in the middle of the etched rib waveguide supporting both TE and TM modes. It has a simple structure and requires no high temperature process like poling. The measured polarization extinction ratio is about 21 dB at the wavelengths of 1.3 and 1.55 /spl mu/m, and the estimated excess loss is about 0.4 dB.     

有机光波导放大器最新进展

稀土掺杂平面光波导放大器是一类重要的光子学元件,它是光通信密集波分复用（DWDM）传输系统的重要组成部分,可以和调制器、光开关、隔离器、阵列波导光栅等任何有损耗的器件集成在一起,补偿光传输过程中的各类损耗。综述了应用于第二（1.33 μm）、第三（1.53 μm）标准通信窗口的有机光波导放大器的研究现状,阐述了不同类型材料制备的器件存在的优缺点、制备过程中存在的问题,并对其发展前景进行了展望。     

A low-loss single-pole six-throw switch based on compact RF MEMS switches

A low-loss single-pole six-throw (SP6T) switch using very compact metal-contact RF microelectromechanical system (MEMS) series switches is presented. The metal-contact MEMS switch has an extremely compact active area of 0.4 mm /spl times/ 0.3 mm, thus permitting the formation of an SP6T MEMS switch into the RF switch with a total area of 1 mm/sup 2/. The MEMS switch shows an effective spring constant of 746 N/m and an actuation time of 8.0 /spl mu/s. It has an isolation loss from -64.4 to -30.6dB and an insertion loss of 0.08-0.19 dB at 0.5-20 GHz. Furthermore, in order to evaluate RF performances of the SP6T MEMS switch, as well as those of the single-pole single-throw RF MEMS series switch, we have performed small-signal modeling based on a parameter-extraction method. Accurate agreement between the measured and modeled RF performances demonstrates the validity of the small-signal model. The SP6T switch performed well with an isolation loss from -62.4 to -39.1dB and an insertion loss of 0.19-0.70 dB from dc to 6 GHz between the input port and each output port.     

基于级联微环谐振器的集成化可重构光学上下路插分复用器

We report on an eight-channel reconfigurable optical add-drop multiplexer based on cascaded microring resonators with a high tuning power consumption and a compact footprint. Microheaters are fabricated on top of the microring resonators and can be modulated using the thermo-optic effect to achieve the reconfigurable functionality of the device. We demonstrate the reconfigurable add-drop multiplexing functionality for channel spacings of 100 GHz and 50 GHz, with the centre wavelengths of the channels aligned to International Telecommunication Union grid specifications. The crosstalk for channel spacings of 100 GHz and 50 GHz are less than..22:5 dB and..15:5 dB, respectively. The average tuning efficiency is about 4.5 mW/nm, and the response speed is about 13.0 kHz.     

基于PSO算法的硅基C波段低损耗紧凑型偏振分束旋转器

提出了一种基于模式演变原理的紧凑型偏振分束旋转器（Polarization Splitter Rotator,PSR）。该器件由锥型TM0-TE1模式转换器与非对称定向耦合（Asymmetric Directional Coupler,ADC）结构的模式分束器组成,经粒子群算法（Particle Swarm Optimization,PSO）和样条插值原理优化后的器件总长度仅为45μm。利用时域有限差分法（Finite Difference Time Domain method,FDTD）对器件进行仿真,数值结果表明：输入TE0模式时,在100 nm(1500～1600 nm)带宽内具有低插入损耗（<0.007 dB）、低串扰（<-28.7 dB）、高偏振消光比（>49.1 dB）;输入TM0模式时,在整个C波段内具有低插入损耗（<0.34 dB）,低串扰（<-47.1 dB）,高偏振消光比（>15.5 dB）,且在中心波长1550 nm处插入损耗值仅为0.06 dB。此外,对器件的公差进行了分析,结果表明该器件具有良好的鲁棒性。所设计的PSR具备低...     

基于FTTH的光网络保护系统的研究

针对FTTH光纤线路的保护问题,提出了一种无源光网络光纤线路切换保护系统.光纤线路切换设备通过不同的光纤链路连接远端设备的两个光通信端口,当某一个与远端设备连接的分支光纤链路出现故障时,光纤线路切换设备通过连接备用的分支光纤链路,保障通信的及时恢复.实验结果表明,ONU能够在50ms内自动完成在光口1和光口2间的识别与光路保护切换,极大地提高了PON光纤线路保护的可靠性和生存性,有利于FTTH/B的应用.     

Silicon oxynitride integrated waveguide for on-chip optical interconnects applications

This work explores the microfabrication technology for realizing miniature waveguide structure for on-chip optical interconnects applications. Thick oxynitride films were prepared by plasma enhanced chemical vapor deposition (PECVD) with N₂O, NH₃ and SiH₄ precursors. The composition and the bonding structure of the oxynitride films were investigated with Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and secondary ion mass spectroscopy. Results showed that the silicon oxynitride deposited with gas flow rates of NH₃/N₂O/SiH₄ = 10/400/10 (sccm) has favorable properties for integrated waveguide applications. The refractive index of this layer is about 1.5 and the layer has comparative low densities of O–H and N–H bonds. The hydrogen bonds can be further eliminated with high temperature annealing of the as-deposited film in nitrogen ambient and the propagation loss can be reduced significantly with thermal annealing. An integrated miniature waveguide with cross-section of 2 μm × 3 μm was realized with the proposed technology. The waveguide is able to transmit signal in either TE or TM mode with propagation loss <0.6 dB/cm (at 1550 nm) and bending radius of about 6 μm.     

一种基于多模干涉波导的超低尺寸波分复用器

波分复用/解复用器作为数据传输的核心器件,广泛应用于片上光互联网络中,其中最重要的指标就是器件的尺寸,插入损耗和串扰大小,为解决传统硅基阵列波导光栅尺寸较大,阵列波导光栅光强不均的问题,我们提出了一种基于绝缘体上硅(SOI)的环形反射器辅助多模干涉波导的四通道波分复用器,可以实现不同通道的波长分离。其核心尺寸仅为10μm×34μm,最小相邻通道串扰为-1442dB。     

Rectangular-core microstructured polymer optical fibre for interconnect applications

A multimode microstructured polymer optical fibre is presented in which a large rectangular core is suspended by thin supporting bridges. Measurements of the near- and far-field patterns, the numerical aperture and polarisation mode-mixing are presented.