基于SOA XGM的波长变换中归零与非归零码的啁啾特性研究  

Chirp Characteristics of Converted Return-to-Zero and Non-Return-to-Zero Signals in SOA XGM Based Wavelength Conversion

作　　者：徐郁 白光富 徐亮 张家豪 Xu Yu;BaiGuangfu;Xu Liang;Zhang Jiahao(College of Physics,Guizhou University,Guiyang,Guizhou 550025,China;Institute of High Energy Physics,Chinese Academy of Sciences,Beijing 100049,China;Hubei Taijing Technology Co.,Ltd.,Suizhou,Hubei 441300,China)

机构地区：[1]贵州大学物理学院,贵州贵阳550025 [2]中国科学院高能物理研究所,北京100049 [3]湖北泰晶科技股份有限公司,湖北随州441300

出　　处：《光学学报》2021年第24期247-256,共10页Acta Optica Sinica

基　　金：国家自然科学基金(61751102,61965004);贵州省教育厅青年科技人才成长项目(黔教合KY字[2018]122);贵州大学SRT项目(2017-10)。

摘　　要：对基于半导体光放大器交叉增益调制效应的全光波长转换后的信号啁啾特性进行了分析。通过数值模拟方法研究了归零码和非归零码经过波长变换后的啁啾及波形变化特征,并研究了两种码型信号的啁啾与光功率、信号速率、波长、信号光消光比、码元波形参数、半导体光放大器偏置电流的关系。结果表明,当码元数量较少时,归零码与非归零码相比,信号会有更大的啁啾;上升沿(下降沿)占比小于10%信号周期时,转换光波形均会出现明显的过冲(下冲)现象,过冲(下冲)导致了转换光的啁啾峰值大于啁啾谷值;增加偏置电流会缓减过冲现象,同时会增加交叉增益效应,偏置电流在不同阶段对啁啾的影响效果是不同的;增大数据传输速率会使载流子浓度的变化加快,导致啁啾峰值(谷值)增加。光注入下增益峰值红移会使转换光啁啾对参考光波长和信号波长具有敏感性;消光比的变化也会改变半导体光放大器中的载流子浓度,进而影响转换光啁啾;增大参考光功率或者降低信号光功率能够导致啁啾降低。研究结果对基于半导体光放大器交叉增益调制效应的全光波长转换系统的实用化具有重要的意义。The chirp characteristics of the converted signals in an all-optical wavelength conversion system based on cross gain modulation of a semiconductor optical amplifier are analyzed.By means of numerical simulation,the chirp and waveform changes of a return-to-zero code and a non-return-to-zero code after wavelength conversion are studied.The relationships of the chirp wirh optical power,signal rate,wavelength,signal extinction ratio,symbol waveform parameters,and bias current of the semiconductor optical amplifier are also studied.The results show that when the number of symbols is small,the return-to-zero code has a larger chirp than the non-return-to-zero code.When the proportion of rising edge(falling edge) is less than 10% of the signal cycle,the converted waveforms of return-to-zero and non-return-to-zero codes both appear obvious the overshoot(down-shoot) phenomenon.The overshoot(down-shoot) causes the chirp peak value of the converted light to be larger than the chirp valley value.Increasing the bias current can reduce the overshoot and enhance the cross gain modulation effect.The effect of bias current on chirp is different at different stages.The increase of data transmission rate accelerates the change of carrier concentration and leads to the enhancement of chirp peak value(valley value).The red shift of the gain peak under light injection makes the chirp sensitive to the reference light and signal wavelengths.The change of extinction ratio can also change the carrier concentration in the semiconductor optical amplifier,which affects the chirp of the converted light.Increasing the reference optical power or decreasing the signal optical power can obtain a lower chirped signal.The results are of great significance to the practical application of an all-optical wavelength conversion system based on the cross gain modulation effect of a semiconductor optical amplifier.

关 键 词：光学器件 半导体光放大器 交叉增益调制 波长变换 啁啾 归零码 非归零码 

分 类 号：O439[机械工程—光学工程]