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Chinese Science Bulletin 2010年第11期55卷 1007-1012页

作者： yan senlin School of Physics and Electronic Engineering Nanjing Xiaozhuang University Nanjing 210017 China

A novel method to enhance the bandwidth of a chaotic carrier from a delayed feedback semiconductor laser transmitter is pre- sented using self-phase modulation (SPM) in an optical fiber external round cavity. A physical model of the laser dynamics is established under the condition of optical feedback light with the SPM effect in the fiber path. A formula for frequency detuning of the optical dual-feedback under SPM is theoretically deduced. The results show that the nonlinear phase shift caused by SPM has an impact on the gain and bandwidth enhancement factor of the laser. The second-order nonlinear effect of the fiber enriches the variety of the amplitudes and phases of the laser while the nonlinear phase shift produces a number of new frequencies, which can spread the bandwidth. Numerical results reveal that with the SPM effect, the bandwidth can be enhanced 4 times more than the bandwidth without it, and the relaxation oscillation frequency of the chaotic laser is increased to 2.56 times more than that of the laser without the fiber path. The enhancement of the chaotic bandwidth can be extended by increasing the optical fiber length, the coupling-feedback ratio, the mirror reflectance and the second order nonlinear coefficient affect.

关键词：光纤非线性效应激光发射器自相位调制混沌载波半导体带宽扫描探针显微镜非线性相移

Control of chaos in an external-cavity multi-quantum-well laser subjected to dual-wedges and optical dual-feedback

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Chinese Science Bulletin 2009年第7期54卷 1158-1163页

作者： yan senlin Department of Physics and Electro-Engineering Nanjing Xiaozhuang University Nanjing 210017 China

A multi-parameter chaos-control method used to control chaos in an external cavity multi-quantum-well (MQW) laser via the dual-wedges and external delayed optical dual-feedback is presented. The physical model of the laser dynamic is established under the conditions of the dual-wedges and dual-feedback light control. The frequency detuning and stable ranges of the control system are theoretically demon-strated. The optical-length of the feedback light may be adjusted by shifting horizontally or sliding the dual-wedges relatively in the external optical road, which will alter the delaying time and feedback in-tensity of the dual-feedback light. Accordingly, the multi-parameter chaos-control of the optical dual-feedback may be achieved physically. The numerical simulations approve that the chaotic laser may be controlled into a stable state, a single-periodic state and multi-periodic states, and the con-trolled periodic pulse power may be increased.

关键词：多量子阱激光器混沌控制光学长度双反馈双楔外腔稳定控制系统反馈控制

Health Monitoring of Long-Haul Fiber Communication System Using Chaotic OTDR

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China Communications 2020年第5期17卷 1-11页

作者： Mengmeng Chen Mingjiang Zhang Shaoxiang Chen Jianguo Zhang senlin yan Yuncai Wang School of Electronic Engineering Nanjing Xiaozhuang UniversityNanjing 211171China Key Lab of Advanced Transducers and Intelligent Control Systems Ministry of Education and Shanxi ProvinceTaiyuan 030024China Institute of Optoelectronic Engineering College of Physics&OptoelectronicsTaiyuan University of TechnologyTaiyuan 030024China School of Electrical and Electronic Engineering The Photonics InstituteNanyang Technological University639798Singapore School of Information Engineering Guangdong University of TechnologyGuangzhou 510006China

A novel chaotic optical time-domain reflectometry(OTDR)-based approach was proposed for monitoring long-haul fiber communication systems with multiple fiber segments. The self-phase modulation and group velocity dispersion effects of the optical cable was considered in demonstrating the proof-of-concept experiment and simulation. In experiments, the correlation peaks are clearly obtained from the correlation trace between the reference and reflected(or scattered) light signals propagating in three optical-fiber segments. The technique affords a high spatial resolution of 2 m, and further long-haul fiber simulations indicate that the sensing distance can be more than 3300 km. Thus, the new proposed technique can be effectively applied for health monitoring of long-haul fiber communication systems.

关键词： fiber communication system chaotic signal optical time domain reflectometry

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双星并联光纤激光同步网络研究

中国激光 2022年第11期49卷 117-126页

作者：颜森林南京晓庄学院电子工程学院江苏南京211171

提出双星光纤激光同步网络,具体研究双星交叉驱动-反相控制并联光纤激光同步网络系统与理论。该网络的结构和光学特点是:先利用双环掺铒光纤激光器构成网络“双星”激光双驱动源;然后采用“双星交叉驱动”对两组并联的多个单环掺铒光纤... 详细信息

提出双星光纤激光同步网络,具体研究双星交叉驱动-反相控制并联光纤激光同步网络系统与理论。该网络的结构和光学特点是:先利用双环掺铒光纤激光器构成网络“双星”激光双驱动源;然后采用“双星交叉驱动”对两组并联的多个单环掺铒光纤激光器进行驱动,由此构成双星交叉驱动两组并联光纤激光网络;最后分别利用“反相位控制与光学驱动”技术实现两组网络并联节点的同步,并进一步实现两组网络并联节点与双星的交叉同步,即实现双星光纤激光同步网络功能。由此设想与构建,给出网络的数学物理光学方程组。从理论上证明了网络并联节点簇同步以及网络节点与双星的交叉同步,形成了网络“星-节点”同步簇理论模式,并成功预测了双“星-节点”并列同步簇的存在。针对两组相互独立并联节点簇的单环掺铒光纤激光器以及作为网络双星的双环掺铒光纤激光器对应激光环的同步进行了数值模拟。本研究发现了网络的单“星-节点”同步簇、混沌同步簇、类周期同步簇、并列双“星-节点”同步簇等。本文还讨论了不同参数条件下双星交叉驱动-反相位控制并联同步光纤激光网络功能的实现。本研究对于光学网络、光纤激光同步网络及其应用具有重要的参考价值。

关键词：光纤光学激光技术光网络同步光纤激光器双星混沌

Atomically dispersed dual Fe centers on nitrogen-doped bamboo-like carbon nanotubes for efficient oxygen reduction

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Nano Research 2022年第3期15卷 1966-1972页

作者： Ligang Ma Junlin Li Zhiwei Zhang Hao yang Xueqin Mu Xiangyao Gu Huihui Jin Ding Chen senlin yan Suli Liu Shichun Mu School of Electronic Engineering Nanjing Xiaozhuang UniversityNanjing 211171China Nanjing Key Laboratory of Optometric Materials and Technology Jinling Institute of TechnologyNanjing 211169China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Key Laboratory of Advanced Functional Materials of Nanjing Nanjing Xiaozhuang UniversityNanjing 211171China Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory Xianhu Hydrogen ValleyFoshan 528200China

Interfacial atomic configuration between dual-metal active species and nitrogen-carbon substrates is of great importance for improving the intrinsic activity of catalysts toward oxygen reduction reaction(ORR).Thus,from the atomic-scale engineering we develop a high intrinsic activity ORR catalyst in terms of incorporating atomically dispersed dual Fe centers(single Fe atoms and ultra-small Fe atomic clusters)into bamboo-like N-doped carbon *** from atomically dispersed dual-Fe centers on the atomic interface of Fe-Nx/carbon nanotubes,the fabricated dual Fe centers catalyst exhibits an extremely high ORR activity(E_(onset)=1.006 V;E_(1/2)=0.90 V),beyond state-of-the-art Pt/***,this catalyst also shows a superior kinetic current density of 19.690 mA·cm^(−2),which is 7 times that of state-of-the-art Pt/***,based on the excellent catalyst,the primary Zn-air battery reveals a high power density up to 137 mW·cm^(−2) and sufficient potential cycling stability(at least 25 h).Undoubtedly,given the unique structure–activity relationship of dual-Fe active species and metal-nitrogen-carbon substrates,the catalyst will show great prospects in highly efficient electrochemical energy conversion devices.

关键词： atomic configuration single Fe atoms atomically dispersed Fe clusters N-doped bamboo-like carbon nanotubes oxygen reduction reaction

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高速多量子阱激光器混沌保密通信系统研究

光学学报 2005年第2期25卷 179-185页

作者：颜森林南京晓庄学院物理系南京210017

　研究了外部光注入高速多量子阱激光器激光混沌全光保密通信系统,导出系统同步方程,理论证明并数值实现了系统的同步,分析了增加反馈系数以缩短同步时间且增强系统同步稳定性的方法。研究分析了多量子阱激光器混沌隐藏和混沌键控保密... 详细信息

　研究了外部光注入高速多量子阱激光器激光混沌全光保密通信系统,导出系统同步方程,理论证明并数值实现了系统的同步,分析了增加反馈系数以缩短同步时间且增强系统同步稳定性的方法。研究分析了多量子阱激光器混沌隐藏和混沌键控保密通信全光调制解调系统模型,数值模拟了具有正弦调制信号的调制频率0.2 GHz混沌模拟保密通信和数字信号调制速率20 Gb/s的混沌数字保密通信以及调制速率0.05 Gb/s混沌键控保密通信的应用,系统确实具有较高的保密性能和反破译能力;分析了混沌数字信号保密通信调制带宽20 Gb/s调制解调时的同步误差以及混沌键控调制速率,系统都具有非常好的调制解调特性,且在高速混沌通信中,系统解调具有相对较小的同步误差,而1 Gb/s是混沌键控通信的速率上限。

关键词：光通信混沌保密多量子阱激光器同步

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光注入半导体激光器分岔与周期研究

光学学报 2009年第4期29卷 996-1001页

作者：颜森林南京晓庄学院物理与电子工程学院江苏南京210017

研究外部光注入半导体激光器的非线性物理特性,用小信号分析方法分析了激光器的动力学行为。分析了外部光注入对半导体激光器的激光非线性频率啁啾影响,给出了最大静态锁模公式,理论上指出,有外部光注入半导体激光器激光频率啁啾不再是... 详细信息

研究外部光注入半导体激光器的非线性物理特性,用小信号分析方法分析了激光器的动力学行为。分析了外部光注入对半导体激光器的激光非线性频率啁啾影响,给出了最大静态锁模公式,理论上指出,有外部光注入半导体激光器激光频率啁啾不再是传统意义上独立的半导体激光器线性啁啾,它和外部注入光以及激光器所处的物理状态有着非常强烈的非线性关系,并随着注入指数的增加而增强,同时,频差以及激光器光线宽增强因子也将起到一定的非线性影响作用。还给出了频差、最大锁模区域、激光分岔条件以及分岔的周期公式。详细地数值模拟了激光随外部光注入频差和注入参数变化所产生的由分岔进入混沌的动力学行为,并数值分析了周期、三周期、多周期、混沌、充分发展混沌过程以及它们的旋转涡旋吸引子、频率、频谱、波形变化,分别算出了最大李雅普诺夫(Lyapunov)指数、静态最大锁模区域和分岔周期,数值给出激光随频率差变化分岔图,逐步认清了该激光系统不稳定动力学行为以及频谱特点。

关键词：激光光学混沌分岔周期

激光混沌交叉发射与交替并行接收在保密通信中应用的基本理论与技术

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中国激光 2020年第9期47卷 223-229页

作者：颜森林南京晓庄学院电子工程学院江苏南京211171

研究了一种新型激光混沌编码系统。该系统将两个空间耦合激光器与另外两个激光器同步,实现了混沌保密通信中的交叉发射和交替并行接收(CEAPR)应用。理论上给出了两个CEAPR的混沌编码和解码方程;定义了激光混沌CEAPR的编码解码数学物理原... 详细信息

研究了一种新型激光混沌编码系统。该系统将两个空间耦合激光器与另外两个激光器同步,实现了混沌保密通信中的交叉发射和交替并行接收(CEAPR)应用。理论上给出了两个CEAPR的混沌编码和解码方程;定义了激光混沌CEAPR的编码解码数学物理原则;实现了两个CEAPR技术方案的应用。系统显著特点是发射混沌编码载波的激光器和接收机激光器具有不同参数(完全不同于传统混沌通信收发同参数密钥系统),且发射源具有多个变量,可实现信息的安全交叉与交替传送,应用灵活,给入侵者从载波上破译通信内容增加了一定的难度。

关键词：光通信混沌激光技术同步编码

增益可调半导体激光器混沌偏振延时双反馈周期的控制方法

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中国激光 2009年第2期36卷 297-301页

作者：颜森林南京晓庄学院物理系江苏南京210017

提出增益可调半导体激光器混沌偏振延时双反馈控制方法,分别建立了垂直正交偏振延时双反馈、偏振π/2转动延时反馈控制以及同偏振面方向延时正负反馈激光动力学物理模型等。通过调节激光器外腔光路中的平面镜可控制一平面偏振反馈光的... 详细信息

提出增益可调半导体激光器混沌偏振延时双反馈控制方法,分别建立了垂直正交偏振延时双反馈、偏振π/2转动延时反馈控制以及同偏振面方向延时正负反馈激光动力学物理模型等。通过调节激光器外腔光路中的平面镜可控制一平面偏振反馈光的延时时间,或调节一偏振反馈光的偏振面到另一个偏振反馈光的偏振面方向上,或者通过偏振器对偏振光进行相位补偿都可以进行激光混沌控制。数值结果证明该方法可以有效控制激光混沌到周期态等。

关键词：物理光学激光混沌控制偏振

Chaotic laser synchronization and its application in optical fiber secure communication

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Science in China(Series F) 2004年第3期47卷 332-347页

作者： yan senlin CHI Zeying CHEN Wenjian Schoof of Electronic Engineering and Photoelectronic Technology, Nanjing University of Science and Technology, Nanjing 210094, China 1. School of Electronic Engineering and Photoelectronic Technology Nanjing University of Science and Technology 210094 Nanjing China

In this paper, optical fiber chaotic secure communication is proposed bycoupling chaotic laser synchronous system with optical fiber propagation channel.Feedback synchronous system of chaotic semiconductor lasers is presented andsynchronous error and decoding formulae are demonstrated. Synchronization betweentwo chaotic laser systems with distributed feedback semiconductor lasers at wavelengthof 1.31 μm is simulatively achieved with almost zero synchronous error. Parametermismatch, synchronous transient response and noise effect on the system are studied.Robustness of synchronization and anti-perturbation can increase by increasing thefeedback coefficient of the system. Influence of group-velocity-dispersion and self-phasemodulation of optical fiber on chaotic laser signal and synchronization are analyzed, and itis found that group-velocity-dispersion affects pulse shape, synchronization and decoding,and limits optical fiber propagation distances, and self-phase modulation does not affectpulse shape, while its product of nonlinear phase shift can affect synchronization anddecoding, and restrict propagation distances of optical fiber chaotic communicationsystem and hence the maximum optical power formula is educed. Injecting parametermodulation and amplitude modulation are numerically simulated in long-haul optical fibersecure communication systems.

关键词： optical fiber chaos synchronization seeure communication