基于半导体光放大器交叉偏振调制的波长转换分析

对半导体光放大器(SOA)中光偏振态发生改变的原因和交叉偏振调制型波长转换进行了探讨和分析.如果SOA具有偏振不灵敏增益,则波长转换效果与泵浦光的偏振态无关,而只与探测光的偏振态有关,而且当入射探测光的偏振与TE模振动方向成45°夹角时,交叉偏振调制的效果最明显.为了使转换效果更好,宜采用反相波长转换,SOA的自发辐射耦合因子β应该很小.     

基于半导体光放大器交叉偏振调制的波长转换分析

对半导体光放大器(SOA)中光偏振态发生改变的原因和交叉偏振调制型波长转换进行了探讨和分析.如果SOA具有偏振不灵敏增益,则波长转换效果与泵浦光的偏振态无关,而只与探测光的偏振态有关,而且当入射探测光的偏振与TE模振动方向成4 5°夹角时,交叉偏振调制的效果最明显.为了使转换效果更好,宜采用反相波长转换,SOA的自发辐射耦合因子β应该很小     

基于半导体光放大器交叉增益饱和的波长转换的理论分析

建立了基于半导体光放大器交叉增益饱和的波长转换的理论模型。分别讨论了小信号下波长转换特性和大信号下转换波形的畸变情况。结果表明,半导体光放大器的载流子寿命是导致输出波形畸变的主要因素。     

基于SOA双泵浦FWM全光波长变换的研究

本文报道了半导体光放大器(SOA)在偏振方向相互垂直的双泵浦光作用下,四波混频(FWM)效应实现的全光波长变换实验,其变换效率和信噪比在55nm的调谐范围内较高并且基本稳定.     

增益钳制半导体光放大器波长转换的研究

数值模拟了增益钳制SOA(GC-SOA)的波长转换过程,分析了GC-SOA实现波长转换的原理.首次发现了GC-SOA波长转换中类似接通延迟的现象,这种现象将限制GC-SOA在高速波长转换中的应用.     

基于级联半导体光放大器中交叉增益调制效应的新型全光逻辑与门

提出一种基于级联半导体光放大器(SOA)中的交叉增益调制(XGM)效应实现的全光逻辑与门新方案。该方案采用单端耦合半导体光放大器提高第一级半导体光放大器输出的消光比，合理控制第二级半导体光放大器的输入光功率，实现了两路2．5Gbit／s非归零(NRZ)信号的逻辑与运算。详细阐明了基于级联半导体光放大器的与门的工作原理和实验方案，分析了实验结果。根据实验结果，发现第一级半导体光放大器输出信号的消光比和信噪比对逻辑与运算结果影响较大，利用单端耦合半导体光放大器后能改善逻辑与运算结果，第二级半导体光放大器的输入抽运光功率对逻辑与运算输出的信号质量有较大的影响。合理控制这些因素，可以有效地提高该逻辑与门的输出特性。     

基于高非线性PCF光纤交叉相位调制的波长转换

设计了一种新型的高非线性低损耗光子晶体光纤(PCF),在1.55μm处可获得35.78W-1·km-1的高非线性系数,损耗为2.5dB/km。提出了一种基于高非线性光子晶体光纤交叉相位调制的波长转换系统,当泵浦光波长为1 565nm、功率为0dBm,信号光波长为1 545nm、功率为10dBm,滤波器波长为1 565.2nm、带宽为0.1nm时,得到最佳的波长转换效应。     

基于半导体光放大器的四波混频型全光波长转换器

本文报道了基于自行研制的半导体光放大器（SOA）的四波混频（FWM）型全光波长转换,采用环型腔掺铒光纤激光器（EDFL）作为泵浦源,实现了转换波长的连续可调。并就波长转换间距、光放大器的小信号增益和输入泵浦光功率对转换效率的影响进行了理论与实验分析,结果表明高的SOA增益和较大的输入泵浦光功率须利于转换效率的提高。     

All-Optical 10 and 40 Gbit/s RZ-to-NRZ Format and Wavelength Conversion Using Semiconductor Optical Amplifiers

We demonstrate that the cross-gain compression (XGC) in a semiconductor optical amplifier can produce effective return to zero (RZ)-to-nonreturn to zero (NRZ) format conversion. This technique is experimentally investigated at 10 and 40 Gbit/s. At 10 Gbit/s, the format adaptation allows for a very high pulsewidth increase, i.e., from 10 to 100 ps. The output 10 Gbit/s NRZ signal is transmitted on metro-like links with no chromatic dispersion compensation.      

Theoretical and Experimental Study of High-Speed Small-Signal Cross-Gain Modulation of Quantum-Dot Semiconductor Optical Amplifiers

We numerically and experimentally investigate the high-speed small-signal cross-gain modulation (XGM) characteristics of a quantum-dot (QD) semiconductor optical amplifier (SOA). From a p-doped QD SOA operating at 1.3 $mu{hbox {m}}$, high-speed small-signal XGM responses up to 40 GHz are measured from low to high injection currents and improve at high injection currents. In the numerical model, we set up about six hundred coupled rate equations, where the carrier dynamics of QD electron and hole states are considered separately and the enhanced hole occupation due to p-type doping is included. The high-speed small-signal XGM spectra are calculated at various modulation frequencies and pump-probe detunings. We identify how the two separate XGM mechanisms of total carrier density depletion (TCDD) at low injection current and spectral hole burning (SHB) at high injection current affect the high-speed small-signal XGM behavior. From the measured and calculated results, we show that high-speed small-signal XGM responses of QD SOAs can be improved by injecting more carriers to the QD excited states, which enhances high-speed XGM induced by SHB rather than by TCDD.      

增益调制型波长转换器消光比均衡的研究

利用半导体光放大器 (SOA)中交叉增益调制 (XGM)效应成功地实现了 62 2 Mb/ s和 2 .5Gb/ s信号的波长转换。对波长上 /下转换性能的研究表明 ,使用增益峰值波长比信号波长长的SOA可以有效地实现上 /下转换效率和消光比均衡 ,从而使这种类型的波长转换器在波分复用器(WDM)全光网中获得更大的应用     

半导体光放大器的偏振调制特性研究

首先理论分析了半导体光放大器的非线性偏振调制（PolM）效应,导出了稳态条件下SOA的偏振转换矩阵。通过数值仿真,描述了包括非线性自偏振调制（SPolM）、互偏振调制（XPolM）导致的偏振态在庞加球上的变化形态。计算结果表明,SOA偏振调制效应表现为偏振旋转特性,偏振旋转的大小由入射光强和偏振态决定,旋转结果表现为输出光中的TM模分量增加,而TE模分量下降。文章同时讨论了SOA驱动电流变化对PolM效应的影响以及由其引起的电光偏振调制（IPolM）效应,并仿真得出了电流变化导致的输出光偏振态的变化轨迹。     

利用半导体光放大器和滤波器组合实现高速波长转换和码型转换

将半导体光放大器(SOA)和滤波器组合使用是实现高速全光信号处理的有效途径。利用半导体光放大器和带宽为0.32nm的可调窄带滤波器同时实现了40Gbit/s的非归零(NRZ)信号的反相波长转换(WC)和非归零到伪归零(PRZ)信号的码型转换,波长转换和码型转换的结果差异取决于滤波器中心波长相对于探测光波长的失谐量。当滤波器的失谐量为-0.24nm时,输出反相的波长转换,此时滤波器起到加速半导体光放大器增益恢复的功能。当滤波器失谐量为 0.41nm和-0.48nm时,得到非归零到伪归零的码型转换,并且产生的伪归零脉冲分别出现在非归零信号的上升沿和下降沿,此时滤波器的作用是将探测光的相位信息转换为强度信息,并且该码型转换结果兼有波长转换的功能。     

Filter‐Free Wavelength Conversion Using Mach‐Zehnder Interferometer with Integrated Multimode Interference Semiconductor Optical Amplifiers

We propose a filter‐free wavelength conversion using a Mach‐Zehnder interferometer with monolithically integrated 2×2 multimode interference semiconductor optical amplifiers (MMI‐SOAs). The device has been optimized by considering a non‐homogeneous carrier distribution due to the self‐imaging properties of the MMI‐SOA. Static measurements show an extinction ratio of up to 18 dB and an input signal rejection ratio of up to 20 dB.     

基于半导体光放大器全光波长转换器的研究进展

详细讨论并分析了三种以半导体光放大器为基础的全光波长转换器的优缺点，并介绍了一些改善性能的最新方案，最后作了一些展望。     

FBG-ECL实现全光波长转换调谐范围的研究

作为自动交换全光网络中的核心器件,全光波长转换器的研究是目前的热点问题。本文基于半导体激光器实现波长转换的理论模型,利用速率方程,通过数值求解不同输入信号波长下的转换波形,得到波长转换间隔对波长转换特性的影响。这对于实用化中,选取适当的输入信号光波长有一定的参考价值。     

Relative Intensity Noise Performance of Wavelength Converters Based on Four-Wave Mixing in Semiconductor Optical Amplifiers

We present a numerical and experimental study of the relative intensity noise (RIN) induced by the four-wave mixing (FWM) based wavelength conversion process in a semiconductor optical amplifier (SOA). The study is based on the RIN evaluation of the converted signal, under various operating conditions (input power levels and wavelength detuning) and input noise characteristics. A detailed numerical model is employed to simulate the FWM process, taking into account the amplified spontaneous emission (ASE) noise, the wavelength dependent gain, and the interaction of four waves in the SOA (two input waves and two product waves). It is shown that for low noise input signals, the output RIN is determined by the power levels of the pump and signal and the wavelength detuning. Operation under saturation allows reduction of the output RIN levels with respect to the input     

基于半导体光放大器的四波混频效应对正交频分复用光信号进行全光波长变换

实验研究了基于半导体光放大器(SOA)的四波混频(FWM)效应的单抽运光正交频分复用(OFDM)信号的波长变换系统.信号光源和抽运光源分别由两个不同输出波长的可调分布反馈式激光器(DFB-LD)产生.信号光源经2.5 Gb/s OFDM的电信号直接调制后再和抽运光源耦合,经光放大器后在SOA实现波长变换.实验结果显示,耦合信号经SOA四波混频效应后,产生新波长的信号光将携带OFDM信号,且转换效率与信号光和抽运光的功率、波长以及两者的偏振夹角有关.同时也测量了转换的OFDM信号的功率-误码曲线和接收星座图.     

半导体光放大器型波长转换器及其小信号分析

本文重点讨论了一种新型的全光器件－波长转换器。从物理概念上分析了它的原理，并且在理论上进行小信号分析，得出有益的结论：当两束光同时入射半导体光放大器，若一束光有变化，会对另一束光进行不同程度的调制，这仅仅表征在幅度与相位上的变化。     

Static Gain, Optical Modulation Response, and Nonlinear Phase Noise in Saturated Quantum-Dot Semiconductor Optical Amplifiers

A rate equation model preserving charge neutrality for quantum-dot semiconductor optical amplifiers (QD-SOAs) is established to investigate the nonlinear gain dynamics in the saturation regime. The static gain of QD-SOA is calculated assuming overall charge neutrality and compared with that without overall charge neutrality. Optical modulation response and nonlinear phase fluctuation through saturated QD-SOAs are calculated numerically based on a small-signal analysis. The gain dynamics of QD-SOAs are strongly dependent on the current injection level. The carrier reservoir in the wetting layer and continuum state is necessary for QD-SOAs to operate with high gain, high saturation power, and ultrafast gain recovery.