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。     

Fabrication of Triplexers Based on Flattop SOI AWG

A triplexer is fabricated based on SOI arrayed waveguide gratings （AWGs）. Three wavelengths of the triplexer operate at different diffraction orders of an arrayed waveguide grating. The signals of 1490nm and 1550nm, which are input from central input waveguide of an AWG, are demultiplexed and the signal of 131Onto, which is input from central output waveguide of an AWG, is uploaded. The tested results show that the downloaded and uploaded signals have fiat-top response. The insertion loss is 9 dB on chip, the nonadjacent crosstalk is less than -30 dB for 1490nm and 1301 nm, and is less than -25 dB for 1550nm, the 3dB bandwidth equates that of the input light source.     

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.     

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。     

32-channel arrayed waveguide grating multiplexer using low loss fluorinated polymer operating around 1550 nm

A 32 × 32 arrayed waveguide grating (AWG) multiplexer operating around the 1550 nm wavelength has been designed and fabricated using highly fluorinated polyethers. The propagation loss of the slab waveguide is about 0.3 dB/cm at 1550 nm wavelength. The channel spacing of the AWG multiplexer is 0.8 nm (100 GHz). The insertion loss of the multiplexer is 10.3-15.3 dB and the crosstalk is less than −20 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。     

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.     

Multimode interference wavelength multi/demultiplexer for 1310 and 1550 nm operation based on BCB 4024-40 photodefinable polymer

A 1310 and 1550 nm coarse wavelength multi/demultiplexer based on benzocyclobutene (BCB 4024-40) polymer is demonstrated for the first time. The device is designed based on a combination of general interference and paired interference mechanisms of multimode interference (MMI). It is fabricated on BK7 glass substrate with a thin layer of SiO₂ as cover. A cost effective chemical etching technique is used in the fabrication process to take advantage of the photosensitive nature of the polymer. The device length was significantly reduced by adopting the restricted multimode interference scheme, lower beat length ratio and cascaded MMI couplers. The measured crosstalk at 1310 nm was 14.4 dB and at 1550 nm was 20.6 dB. The measured insertion loss is around 3.2-3.5 dB for both ports.     

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.     

SOI波长信号分离器的研制

根据大截面单模脊形波导理论和双模干涉机制，在硅片直接键合、背面抛光减薄的ＳＯＩ材料上，通过氢氧化钾各向异性腐蚀的方法，成功地研制出ＳＯＩ波长信号分离器，在波长为１．３μｍ，其插入损耗为４．８１ｄＢ，串音小于－１８．６ｄＢ。     

Novel optical add-drop multiplexer based on dual racetrack resonators

In this paper, we designed and fabricated a four-channel optical add-drop multiplexer (OADM) based on dual racetrack resonators. The size of the fabricated device is only 2400 μm × 500 μm. The fabricated device can effectively and perfectly realize the signals upload and download. The free spectral range (FSR) of OADM is about 15.2 nm. We take the spectral responses near 1555 nm as an example. When the device acts as an optical drop multiplexer, the minimum insertion loss is 4.481 dB and the maximum extinction ratio is 31.931 dB. The maximum adjacent channels crosstalk is -9.845 dB. When the device acts as an optical add multiplexer, the minimum insertion loss is 0.944 dB and all of the extinction ratios are bigger than 25 dB. The maximum crosstalk is -16.531 dB which indicates the crosstalk can be neglected.     

Low Loss Polarization Maintaining Photonic Crystal Fiber

A low loss polarization maintaining photonic crystal fiber has been fabricated. The fiber loss was 1.3 dB/km at 1550 nm. The polarization crosstalk for a 100-m fiber was ?5 dB at 1550 nm.     

Design and Fabrication of Micromechanical Optical Switches Based on the Low Applied Voltage

A micromechanical optical switch driven by electrostatic was fabricated with (100) silicon and tilted 2.5°(111) silicon. The pull-in voltage is 13.2V, the insertion loss is less than 1.4dB, the crosstalk is less than -50 dB.     

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.     

聚合物微环电光开关的模拟和优化

利用耦合模理论、电光调制理论和微环谐振理论,提出一个完善合理的聚合物微环电光开关的器件模型,并给出了可用以分析微环谐振过程的光强传递函数,据此在谐振波长1 550 nm下对该器件进行了模拟和优化.结果表明：微环波导芯截面尺寸为1.8×1.8 μm2,波导芯与电极间的限制层厚度为1.1 μm,电极厚度为0.15 μm,微环半径为15.2 μm,微环与信道间的耦合间距为0.16 μm,光绕微环转300 圈即可形成稳定的谐振状态,此时的谐振时间约为147.4 ps.不加电压时,下信道的插入损耗约为0.8 dB,上信道的串扰约为－26 dB;当取工作电压等于19.7 V为开关电压时,上信道的插入损耗约为0.34 dB,下信道的串扰约为－20 dB.     

Low-Loss 256-Channel AWG Module with Monolithically Integrated Spot-Size Converters

We developed a compact fiber-pigtailed 256-channel AWG module with 1.5% △ waveguides.By monolithically integrating spot-size converters with input/output waveguides, we achieved a lowinsertion loss of 2.6-4.1 dB with a low background crosstalk of -40 dB.     

降低AWG插入损耗和串扰设计新方法

在AWG器件的设计中引入了抛物线型的楔形波导结构,根据过渡区理论优化了引入的抛物线型楔形结构的形状和尺寸.采用抛物线型楔形结构代替直线型楔形结构,AWG的插入损耗降低了2 dB左右.在优化参数时使输出/输入波导间距与阵列波导间距取不同的值,并使输出/输入波导间距适当增大,而阵列波导间距取较小值,这样使得串扰降至－30 dB以下且插入损耗保持在低水平.运用光束传播方法给出器件的输出光谱并证实了理论上预想的结果.     

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。     

阵列波导光栅平坦化的研究

阵列波导光栅的平坦化在实际应用中有很重要的意义.本文系统地研究了阵列波导光栅的平坦化.在输入波导、输出波导、阵列波导输入端与输出端上分别引入了指数型锥形波导.通过改变锥形波导的形状和尺寸来实现平坦化的优化.本文首先从理论上论述了引入指数型锥形波导的输出光谱特性,给出了结构参量的关系表达式,阐明了输入波导处的锥形波导是影响输出光谱平坦化的主要因素,阵列波导和输出波导处的锥形波导对输出光谱的平坦化有一定的影响.其次采用数值模拟的方法模拟了输出光谱,优化了结构参量,总结出了指数型锥形波导对平坦化影响的趋势和规律.模拟结果显示,输出光谱1 dB带宽大于通道间隔的50%,插入损耗从5.2 dB减小到了4.0 dB,串扰小于-30 dB.最后,本文给出了实验结果,插入损耗减小了0.87 dB,串扰减小了3.67 dB,1 dB带宽增加0.1 nm,增加了54.7%.实验结果表明引入指数型锥形波导提高了阵列波导光栅器件的光谱性能.     

An integrated reconfigurable optical add-drop multiplexer based on using an opto-VLSI processor and a 4-f imaging system

A novel integrated reconfigurable optical add-drop multiplexer (ROADM) structure is proposed and demonstrated experimentally. The ROADM employs an interface substrate that enables the integration of a fiber-lens collimator array and an Opto-VLSI processor to realise a 4-f imaging system through optical beam steering. Phase hologram optimization of the Opto-VLSI processor is investigated, for maximizing the number of wavelength channels while keeping adequate insertion loss and crosstalk levels. Experimental results are shown, which demonstrate a broadband operation and the principle of the ROADM with crosstalk of less than −30.5 dB and insertion loss of less than 6 dB for the drop and through operation modes.