Author Affiliations
Abstract
1 Key Laboratory of Optoelectronic Materials and Devices, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
2 Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
Expanding the optical communication band is one of the most effective methods of overcoming the nonlinear Shannon capacity limit of single fiber. In this study, GeSn resonance cavity enhanced (RCE) photodetectors (PDs) with an active layer Sn component of – were designed and fabricated on an SOI substrate. The GeSn RCE PDs present a responsivity of 0.49 A/W at 2 μm and a 3-dB bandwidth of approximately 40 GHz at 2 μm. Consequently, Si-based 2 μm band optical communication with a transmission rate of 50 Gbps was demonstrated by using a GeSn RCE detector. This work demonstrates the considerable potential of the Si-based 2 μm band photonics in future high-speed and high-capacity optical communication.
Photonics Research
2024, 12(4): 767
Author Affiliations
Abstract
1 State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
2 Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
High-performance germanium (Ge) waveguide photodetectors are designed and fabricated utilizing the inductive-gain-peaking technique. With the appropriate integrated inductors, the 3-dB bandwidth of photodetectors is significantly improved owing to the inductive-gain-peaking effect without any compromises to the dark current and optical responsivity. Measured 3-dB bandwidth up to 75 GHz is realized and clear open eye diagrams at 64 Gbps are observed. In this work, the relationship between the frequency response and large signal transmission characteristics on the integrated inductors of Ge waveguide photodetectors is investigated, which indicates the high-speed performance of photodetectors using the inductive-gain-peaking technique.High-performance germanium (Ge) waveguide photodetectors are designed and fabricated utilizing the inductive-gain-peaking technique. With the appropriate integrated inductors, the 3-dB bandwidth of photodetectors is significantly improved owing to the inductive-gain-peaking effect without any compromises to the dark current and optical responsivity. Measured 3-dB bandwidth up to 75 GHz is realized and clear open eye diagrams at 64 Gbps are observed. In this work, the relationship between the frequency response and large signal transmission characteristics on the integrated inductors of Ge waveguide photodetectors is investigated, which indicates the high-speed performance of photodetectors using the inductive-gain-peaking technique.
germanium photodetectors inductive-gain-peaking optical interconnection Journal of Semiconductors
2023, 44(1): 012301
提出一种基于视觉密码的远距离光学信息认证系统。该系统可将远处的视觉密钥通过望远镜系统与系统内的视觉密钥配对实现非相干叠加以完成认证操作,减少了共享密钥的人为传递过程,也解决了实际应用中密钥携带运输不方便的问题。而且,在整个提取过程中视场受限于系统,仅操作者能在系统内看见认证信息,其他人即便在附近也无法查看,加强了信息显示和复现的安全性。认证的过程仅需要操作者将两块共享密钥仔细对准即可,无需其他的光学和密码学知识,整个过程简单高效。此外,光学实验也证明了该系统可应用于实际且具有很高的安全性。
几何光学设计 远距离光学信息认证 视觉密码学 显示安全 光学学报
2021, 41(16): 1607001
1 中国电子科技集团公司第三十八研究所, 安徽 合肥 230000
2 安徽省天线与微波工程实验室, 安徽 合肥 230000
提出了一种基于可调光延迟线的微波光子正交解调技术,并基于该技术设计了微波光子零中频接收机。通过调节光延迟线实现本振信号的90°移相,并采用波分复用方法在共用的级联马赫-曾德尔调制器结构中实现两条正交链路的射频信号与本振信号的混频,从而提高了光正交解调的幅相一致性。所设计的微波光子零中频接收机可对光正交解调之后的中频处理器件如光电探测器、滤波器以及模数转换器等引起的链路幅相不平衡进行数字补偿。经数字幅相失衡补偿后,微波光子零中频接收机在中心频率为12 GHz、瞬时带宽为4 GHz的工作频段内测得幅度不平衡小于0.4 dB,相位不平衡小于1.5°,镜频抑制度大于45 dB,最高镜频抑制度可达79 dB。
光通信 微波光子 宽带接收机 零中频 镜频抑制
1 中国科学技术大学环境科学与光电技术学院, 安徽 合肥 230026
2 中国科学院安徽光学精密机械研究所大气物理化学研究室, 安徽 合肥 230031
3 中国科学技术大学研究生院, 安徽 合肥 230026
利用自行研制的气溶胶飞行时间质谱仪(aerosol time-of-flight mass spectrometer, ATOFMS)对气溶胶粒子的折射率进行测量。 首先利用ATOFMS对气溶胶粒子的粒径和光散射强度进行测量,然后由Mie散射理论结合ATOFMS光散射区域的几何结构,推算出光电倍 增管接收的理论光通量与气溶胶粒子的大小和折射率之间的函数关系。通过比较实验测量的气溶胶粒子光散射平均强度与Mie散射 理论值,对粒子的折射率进行反演。与实际样品数据参数对比的结果表明该方法是可行的。
气溶胶 飞行时间质谱仪 光散射 反演 折射率 aerosol time-of-flight mass spectrometer light scattering inversion refractive 大气与环境光学学报
2017, 12(5): 349
1 中国科学院安徽光学精密机械研究所中国科学院大气成分与光学重点实验室, 安徽 合肥 230031
2 中国科学技术大学研究生院, 安徽 合肥 230026
3 中国科学院安徽光学精密机械研究所大气物理化学研究室, 安徽 合肥 230031
4 中国科学技术大学环境科学与光电技术学院, 安徽 合肥 230026
离子诱导成核是大气气溶胶形成的重要路径之一。大气中团簇离子的形成,主要由宇宙射线电离空气产生的初级离子 与H2 O、H2 SO4 、HNO3 、NH3 、有机物等物质发生的离子-分子反应而产生。成核是团簇离子生长和蒸发相互竞争的一个过程,团簇离子生 长到临界核尺寸时,便可自发生长。研究表明临界核大小约1.6 nm,对应粒子的质量数在5000 amu以上。离子诱导生成的气溶胶粒子对气候的影响以 及离子诱导成核在大气成核事件中是否占主要作用还存在很大争议,这需要进行进一步的外场观察、理论模拟、实验室研究来充分弄清离子诱导成核机理。
离子诱导成核 气溶胶 团簇离子 临界核 宇宙射线 气候 ion-induced nucleation aerosol cluster ions critical nucleus cosmic ray climate
哈尔滨工业大学 深圳研究生院 高速光通信公共服务平台,广东 深圳 518055
基于电吸收调制器,对比分析了无延时干涉仪装置和有延时干涉仪装置条件下波长变换的情形.10 Gb/s归零码光信号波长变换的实验证明，延时干涉仪装置可有效消除变换后光信号的脉冲拖尾，并极大地改善信号的消光比指标.分析了电吸收调制器偏置电压、数据信号功率、变换波长等工作参数对波长变换性能的影响，发现无论有无延时干涉仪装置，均需合理设置偏置电压来优化波长变换信号的接收灵敏度；在-3.0 V偏置电压条件下，有延时干涉仪装置时，灵敏度增益达2.0 dB.
电吸收调制器 延时干涉仪 交叉吸收调制 波长变换 消光比 Electroabsorption modulator Delayline interferometer Crossabsorption modulation Wavelenght conversion Extinction ratio
Author Affiliations
Abstract
We propose a dither-free 8-phase-shift-keying (8PSK) generator control scheme for adjusting the bias voltage of Mach–Zehnder modulator (MZM) and the electrical driver signals of two cascaded phase modulators (PMs). The control module includes a delay-line interferometer (DLI), a balanced photo-detector (BPD), and asynchronous sampling data processing. Both analysis and simulation results show that the bias voltage and the driver signal amplitude control can be achieved independently between these cascaded modulators with only one tap point and one control configuration. Finally, the influence of the bit number of A/D converter (ADC) for asynchronous sampling is also discussed for the practical implementation.
060.2330 Fiber optics communications 060.4080 Modulation 060.4510 Optical communications Chinese Optics Letters
2014, 12(s1): S10606
Author Affiliations
Abstract
We propose a reconfigurable 8PSK/8QAM modulator implementation by employing two cascaded QPSK modulators with an interferometer in between. With simple control of bias voltage of the interferometer, a flexible switching between 8PSK/8QAM can be achieved. The transmission performance of the generated 8PSK/8QAM signals over different link scenarios is compared via numerical simulations. The results reveal that the proposed implementation has the capability of maximizing transmission distance in the case of ynamic optical network.
060.0060 Fiber optics and optical communications 060.5060 Phase modulation Chinese Optics Letters
2014, 12(s1): S10605
哈尔滨工业大学深圳研究生院电子与信息工程学院， 广东 深圳 518055
分析了由两种光调制结构产生的高阶调相非归零码的码间跃变图案，并以此来研究码间跃变图案与光滤波性能间的关系。串行调制器方案下，部分跃变图案为曲线型，而在并行调制器方案下，所有的码间跃变图案本征均为直线型。可以证明，码间跃变图案特性对光滤波特性存在重要影响。在串行调制器方案下，光滤波可以导致明显的跃变图案依赖性。相对而言，并行调制方案有更小的眼睁开代价，因此具有更好的窄带滤波容忍性。最后，研究了在解调器参数优化下接收机灵敏度随光滤波带宽的变化曲线。
光通信 码间跃变图案 谱效率 相移键控 窄带滤波 中国激光
2014, 41(s1): s105008
