可调谐双波长低抖动增益开关光脉冲的产生

提出了一种产生可调谐双波长低抖动超短光脉冲的新方法。采用外光注入法来降低增益开关F-P激光脉冲的时间抖动,实现了脉冲光谱的双波长可调谐输出。实验中利用两个多量子阱DFB激光器作为外部种子光源,通过温度控制和偏振态调节使外部种子光有效地耦合到增益开关F-P激光器中,输出的光脉冲时间抖动(均方根)从2.57ps降低至1.06ps,双波长的边模抑制比可达25dB。通过改变DFB激光器和F-P激光器的工作温度,可实现波长从1540nm到1560nm的可调谐输出。     

10GHz低抖动增益开关DFB激光器

采用国产管芯,利用增益开关效应获得了10GHz超短光脉冲.利用自注入的方法,采用最简单的结构,减小了增益开关DFB激光器光脉冲的时间抖动,使10GHz光脉冲的时间抖动小于840fs.研究了光脉冲抖动量对温度变化及微波驱动频率的敏感性.利用线性压缩和梳状色散渐减光纤链获得10GHz、5ps无基座光脉冲.     

10GHz低抖动增益开关DFB激光器

采用国产管芯,利用增益开关效应获得了10GHz超短光脉冲.利用自注入的方法,采用最简单的结构,减小了增益开关DFB激光器光脉冲的时间抖动,使10GHz光脉冲的时间抖动小于840fs.研究了光脉冲抖动量对温度变化及微波驱动频率的敏感性.利用线性压缩和梳状色散渐减光纤链获得10GHz、5ps无基座光脉冲.     

10GHz低抖动增益开关DFB激光器

采用国产管芯 ,利用增益开关效应获得了 10 GHz超短光脉冲 .利用自注入的方法 ,采用最简单的结构 ,减小了增益开关 DFB激光器光脉冲的时间抖动 ,使 10 GHz光脉冲的时间抖动小于 840 fs.研究了光脉冲抖动量对温度变化及微波驱动频率的敏感性 .利用线性压缩和梳状色散渐减光纤链获得 10 GHz、 5 ps无基座光脉冲     

增益开关半导体激光器的三级脉冲整形方案

增益开关半导体激光器产生的光脉冲宽度往往较宽,且具有一定大小的脉冲基座。为了提高增益开关半导体激光器的脉冲质量,提出了一种三级脉冲整形方案。首先,利用色散补偿光纤将增益开关半导体激光器输出的光脉冲宽度从39.381 ps压缩到26.681 ps,随后利用掺铒光纤放大器和色散位移光纤的高阶孤子效应进一步将光脉冲的宽度压缩到20.916 ps,最后利用半导体光放大器的自相位调制效应区分开脉冲基座与脉冲中心的光谱,并利用光滤波器滤除脉冲基座对应的光谱部分,从而消减脉冲基座,并将脉冲宽度压缩到18.497 ps。实验结果表明,该三级脉冲整形方案可以有效地压缩脉冲宽度以及减小脉冲基座,从而提高增益开关半导体激光器输出光脉冲的质量。     

1.06μm注入锁定增益开关半导体激光器特性分析与功率放大研究

报道了1.06 m增益开关半导体激光器的详细特性分析和功率放大研究。用高频正弦信号调制中心波长1.06 m的F-P腔半导体激光器得到脉宽约为100 ps、平均功率约为20 mW,重频从500 MHz到2 GHz连续可调的稳定短脉冲激光输出。采用注入锁定改善增益开关半导体激光器的输出特性。研究和分析了调制信号的频率、功率和偏置电流的大小以及注入锁定的功率、温度对激光器输出特性的影响。将该激光器作为种子,用108 W的抽运光进行两级全光纤功率放大得到了82 W的高功率输出,光光转换效率达到76%。     

低时间抖动的增益开关型被动调Q激光器

被动调Q激光器的输出抖动一般较大,为了降低这一输出时间抖动,同时实现激光器的小型化,可以根据增益开关工作原理,利用电源控制抽运功率密度变化,实现被动调Q情况下的增益开关.根据这一原理研制了环形激光二极管(LD)抽运增益开关调Q激光器.这种新型被动调Q激光器的输出能量为30 mJ,输出脉冲宽度约16 ns.实验中将传统的两套抽运源减少为一套,通过控制电源波形直接形成抽运功率的增益台阶脉冲,减少了影响时间跳动的因素.多发次统计测量结果表明,激光脉冲与电源输出外触发信号的时间抖动小于1 μs.根据测量的抽运预脉冲功率稳定性和阶跃脉冲的瞬时抽运功率计算的输出抖动与实验结果基本相符.     

半导体激光器皮秒光脉冲产生技术

本文概述半导体激光器皮秒(ps)光脉冲产生的方法,这些方法包括锁模、增益开关、电反馈、光电反馈和Q开关等,并报道了各种方法产生ps光脉冲的现有水平及未来展望。     

取样光栅分布反馈激光器阵列器件研究

采用了一种基于取样光栅原理制作多通道增益-折射率耦合型光栅的方法,成功制作了8波长分布反馈(DFB)激光器阵列,阵列中各激光器的阈值电流为30～40 mA,注入电流为100 mA时的平均输出光功率为10mW,阵列器件实现了波长的可选择性激射,相邻激光器间的频率间距为200 GHz,验证了用取样光栅方法制作DFB激光器阵列的可行性。     

半导体激光器混沌相位共轭反馈控制方法

提出了半导体激光器混沌相位共轭反馈(PCF)控制方法,建立了相位共轭反馈控制条件下激光器电流激发混沌的物理模型,发现其混沌控制物理机制是相位共轭反馈影响改变了激光器非线性增益和线宽增强因子特性,控制了系统的动力学行为及频率特性,其影响程度与反馈系数、延迟时间和光线宽增强因子等有关。数值模拟结果表明,在不同强度的光反馈下,通过调节相位共轭反馈光的延迟时间可以控制混沌激光到周期态、双周期态、多周期态等;发现相位共轭反馈控制特点是反馈光场和输出激光处于相干增强状态去实现混沌控制,且能控制实现激光器功率增强的周期脉冲输出。     

Generation of low jitter and discrete tunable dual-wavelength optical pulses at arbitrary repetition rates

Recently there is an increasing interest in generatingshort optical pulses with lowti ming jitter and tuneablemulti-wavelength due toitsi mportant applicationin op-tical ti me division multiplexed(OTDM),wavelength di-vision multiplexed(WDM)systems,and opt…     

Measurement and simulation of the turn-on delay time jitter ingain-switched semiconductor lasers

The turn-on delay time jitter of four different unbiased gain-switched laser types was determined by measuring the temporal probability distribution of the leading edge of the emitted optical pulse. One single-mode 1.5-μm distributed feedback laser and three multimode Fabry-Perot lasers emitting at 750 nm and 1.3 μm were investigated. The jitter was found to decrease for all lasers with increasing injection current. For multimode lasers it decreases from 8 ps excited slightly above threshold down to below 2 ps at three times the threshold current. The jitter of the distributed feedback (DFB) laser is a factor of 3-5 larger than the jitter of the three multimode lasers. A model for predicting the turn-on delay time jitter is presented and explains the experiments quantitatively     

高消光比超短脉冲产生的实验研究

实验研究了一种高消光比短脉冲的产生技术。利用色散补偿光纤线性压缩由增益开关分布反馈激光器出射的光脉冲。而后利用电吸收调制器的非线性吸收特性同步调制光脉冲。利用这种方法在实验上产生了重复频率为10GHz，脉宽为10．4ps，抖动小，高消光比，无基座的短脉冲。此种技术可以应用于40Gbit／s的光时分复用系统中，同时也说明电吸收调制器具有同号脉冲整形功能。     

Dual Semiconductor Laser System With Rapid Time-Delay for Ultrafast Measurements

We present a dual semiconductor laser system at 1.55 mum with femtosecond pulse widths and very low timing jitter for rapid pump-probe measurements. Synchronizing the two lasers to the same low-noise radio frequency-oscillator allows the use of an electrical phase shifter for the relative time delay between the lasers. This leads to a large scanning window that nearly matches the pulse period of 2.5 ns, as well as achieving a discrete time step of below 100 fs. The timing jitter of the complete dual laser system including all electronics is only 540 fs across the whole time delay. The nonlinear pulse compression using especially designed comb-like dispersion profiled fiber leads to autocorrelation widths of 310 fs. The system performance, i.e., the high time resolution is demonstrated by optical cross correlation of the pump and probe pulse, showing a very low full-width at half maximum of 1.3 ps     

A high-speed optical star network using TDMA and all-opticaldemultiplexing techniques

The authors demonstrate the use of time-division multiplexing (TDM) to realize a high capacity optical star network. The fundamental element of the demonstration network is a 10 ps, wavelength tunable, low jitter, pulse source. Electrical data is encoded onto three optical pulse trains, and the resultant low duty cycle optical data channels are multiplexed together using 25 ps fiber delay lines. This gives an overall network capacity of 40 Gb/s. A nonlinear optical loop mirror (NOLM) is used to carry out the demultiplexing at the station receiver. The channel to be switched out can be selected by adjusting the phase of the electrical signal used to generate the control pulses for the NOLM. By using external injection into a gain-switched distributed feedback (DFB) laser we are able to obtain very low jitter control pulses of 4-ps duration (RMS jitter <1 ps) after compression of the highly chirped gain switched pulses in a normal dispersive fiber. This enables us to achieve excellent eye openings for the three demultiplexed channels. The difficulty in obtaining complete switching of the signal pulses is presented. This is shown to be due to the deformation of the control pulse in the NOLM (caused by the soliton effect compression). The use of optical time-division multiplexing (OTDM) with all-optical switching devices is shown to be an excellent method to allow us to exploit as efficiently as possible the available fiber bandwidth, and to achieve very high bit-rate optical networks     

10 GHz超低抖动光短脉冲源

报道了一种新型的重复频率为10 GHz,脉宽为5.3 ps,抖动为184 fs的高稳定光短脉冲源.将大信号调制半导体激光器产生的10 GHz光脉冲,先送入LiNbO3电光相位调制器增强负啁啾,并使光谱进一步展宽,再通过色散补偿光纤(DCF)压缩脉冲啁啾,可得到光短脉冲.由于大信号调制激光器输出的光脉冲本身具有负啁啾,而通过相位调制器的光脉冲在不同的时间间隔内既有正啁啾也有负啁啾,通过适当调整进入相位调制器的光脉冲时延,使其通过相位调制器后累加产生更大的负啁啾,再利用正色散光纤压缩啁啾,从而得到低抖动且无基座的光短脉冲.     

Correlated and uncorrelated timing jitter in gain-switched laserdiodes

The author describes correlated and uncorrelated timing jitter of gain-switched pulses generated from sinusoidally modulated laser diodes measured from photocurrent power spectra. It is found that if dc bias is decreased to obtain shorter pulses, then the root-mean-square (rms) value of uncorrelated timing jitter drastically increases to more than 2 ps, while correlated jitter remains constant at the drive circuit level of ~0.2 ps. By optimizing the bias condition and compression fiber length, total timing jitter of gain-switched pulses can be reduced to as low as ~0.5 ps, as their pulse width is kept less than 10 ps     

100-GHz soliton pulse train generation using soliton compression oftwo phase side bands from a single DFB laser

A 100-GHz soliton pulse train, with the potential of very low timing jitter, is generated using soliton compression of the beat signal between two optical carriers. The optical carriers are obtained by optically filtering out the third-order sidebands generated from a single DFB laser and a LiNbO₃ electro-optic phase modulator driven at 16.9 GHz