单模半导体激光器等效电路模型

介绍了单模半导体激光器的大信号、小信号及噪声等效电路模型，给出了确定模型参数的一般方法，并在ＰＳＰＩＣＥ中以电路宏模型的方式实现了激光器的大信号模型，对激光器小信号调频响应和大信号非线性失真特性进行了计算机时域模拟。     

一个简单的量子阱激光器等效电路模型

给出一个新的量子阱激光器等效电路模型,由量子阱激光器单模速率方程推导得到并在电路模拟程序ＳＰＩＣＥ中完成。该模型考虑了热辐射效应和分离限制区域（ＳＣＨ）内的载流子工作情况,给出了新的光增益表达式。并利用该模型对单量子阱激光器的小信号特性和瞬态大信号特性进行了预测,模拟结果表明和速率方程的直接求解结果吻合很好。     

直接调制半导体激光器非线性失真的计算机辅助分析

根据半导体激光器的归一化速率方程建立了大信号等效电路模型，运用ＰＳＰＩＣＥ电路分析软件分析了其非线性失真，并与实测结果作了比较，二者吻合很好。     

基于等效电路模型的半导体激光器直流偏置分析

从传统的激光器速率方程出发,同时考虑芯片封装寄生参量和本征区接触参量的影响,得出一种双异质结半导体激光器的新型等效电路模型,在此模型基础上用电路仿真软件PSpice分析了直流偏置对激光器弛豫振荡、小信号频率响应、大信号脉冲响应的影响。     

增益饱和对半导体激光器调制特性的影响

本文用小信号分析法建立了半导体激光器调制的数学模拟，用这个模型研究了增益饱和对半导体激光器的功率调制，波长调制和ＣＰＲ值的影响。     

光纤通信系统中光源特性的模拟

利用单模激光器速率方程，对光纤通信系统中光源的静态和动态特性进行了数值模拟。研究了P-I特性和小信号模型下光源的调制响应，分析了信号传输速率、半导体激光器偏置电流和线宽增强因子对输出脉冲的啁啾特性的影响，从而有助于半导体激光器的设计和光纤通信系统的性能优化。     

大信号直接调制半导体激光器的谐波非线性失真特性研究

本文对微波副载波光纤传输中最关心的大信号调制半导体激光器的谐波非线性进行了理论与实验研究。在ＬＤ速率方程的基础上，建立了一个适合计算谐波失真特性的分析模型。同时，对这一个国产１．５５μｍＩｎＧａＡｓＰＤＣ－ＰＢＨ－ＤＦＢ－ＬＤ的二次与三次谐波特性进行了测量，结果与理论计算值一致。     

实用化宽带半导体激光器组件的研制及其特性的研究

使用ＤＣ－ＰＢＨ型激光二极管芯片，设计制作了实用化封装形式的宽带半导体激光器组件，在理论上和实验上研究了组件的封装模型、小信号频率调制特性和非线性失真，其光响应为３ｄＢ，带宽大于２ＧＨｚ．该器件可满足六次群光通信系统的带宽要求，也可用于ＧＨｚ级微波副载波光通信系统．     

连续波超音速氧碘激光器小信号增益数值模拟研究

氧碘激光器是目前波长最短的化学激光器,受到了人们的普遍关注,近年来发展迅速.氧碘激光器的研究涉及气动力学、化学反应动力学和高能激光物理等众多学科.作者曾采用预混模型,对氧碘激光器的光腔流场和小信号增益进行了数值模拟,研究了不同化学配比条件对光腔流场和小信号增益的影响.本文在此研究基础上,根据氧碘激光器的实际混合过程,建立二维数值模拟模型,对氧碘激光器的光腔流场和小信号增益进行了计算,比较了两种混合模型对计算结果的影响,研究了不同化学配比条件对计算结果的影响.(PC2)     

增益非线性参数对半导体激光器调制特性的影响

本文用小信号分析法建立了半导体激光器调制的数学模拟，用这个模型研究了增益与载流子密度的非线性依赖关系对半导体激光器的功率调制、波长调制和ＣＰＲ值的影响。     

用多模半导体激光器实现动态定位的研究

提出了一种新的半导体激光定位技术。它利用多模半导体激光器的光谱分布引起的干涉条纹的强度分布来确定等光程差点。干涉仪体积小，信号处理简单，系统性能稳定，可以在大范围内捕捉零点。     

单量子阱激光器小信号频响特性模拟分析

量子阱激光器具有优良的性能 ,是宽带通信的重要光源。基于三层速率方程的量子阱激光器模型在明确引入了过渡态的概念后 ,对于量子阱中载流子的传输过程就有了更完整的描述。文中运用三层速率模型 ,对小信号调制下单量子阱激光器的频率响应进行模拟分析。与公开发表的文献资料比较 ,所设计的模型精度高 ,易于分析 ,有实用意义。     

Analysis of delay-and-multiply optical FSK receivers withline-coding and non-flat laser FM response

We present a theoretical analysis of the performance of coherent optical FSK systems when the driving laser signal is AMI or Manchester (biphase) line-coded to counteract the nonideal FM characteristic of the transmit laser diode, and the received signal is heterodyned and detected by a delay-and-multiply demodulator. The analysis takes into account IF filtering by assuming linear filtering of the noisy signal phase, accounting, for small linewidths, for laser phase noise in a straightforward and accurate manner. A simple equivalent baseband model of the system is derived for performance evaluation, applicable to both cases of large demodulator delay and when the delay tends to zero (ideal discriminator). Noise statistics include the clicks due to both signal and phase noise. The problem of performance evaluation is reduced to a classical intersymbol interference problem which is solved by mead of the method of Gauss quadrature rules. The analysis accurately predicts the effectiveness of AMI and Manchester line coding, depending on several system parameters such as linewidth, modulation index, IF bandwidth and laser FM response, and can be easily extended to other line coding techniques     

1047 nm laser diode master oscillator Nd:YLF power amplifier laser system

A master oscillator power amplifier (MOPA) laser transmitter system at 1047 nm wavelength using a semiconductor laser diode and a diode pumped solid state (Nd:YLF) laser (DPSSL) amplifier is described. A small signal gain of 23 dB, a near diffraction limited beam, l Gbit/s modulation rates and >0.6 W average power are achieved. This MOPA laser has the advantage of amplifying the modulation signal from the laser diode master oscillator (MO) with no signal degradation.<>     

单模半导体激光器噪声特性预测

本文在Harder小信号半导体激光器噪声等效电路模型的基础上,与直接求解单模速率方程相结合,给出了一个等效噪声网络模型,并且利用该模型对LD的噪声特性进行了预测。     

Dynamic response of colliding-pulse mode-locked quantum-well lasers

The colliding-pulse mode-locked scheme, using quantum-well semiconductor lasers, has been reported to be useful for the generation of short optical pulses with a high repetition rate. In this paper, the large signal dynamic process of a monolithic colliding-pulse mode-locked laser diode is simulated using a large signal laser model. The refractive index changes induced by variations of the carrier density and the standing wave effect in the saturable absorber have been taken into account in the simulation     

半导体激光自混合变速测量的离散Chirp-Fourier变换方法

当外部激光被反射回激光内腔时,反馈光与激光器腔内光混合,调制激光器的输出功率和频率,通过信号处理可以得到物体运动的多普勒频率,从而计算出物体的运动速度。基于这种特性,设计出一种激光自混合干涉仪,为了知道该技术是否适用于变速测量,对激光自混合用于变速运动物体的速度测量进行了探索。基于激光自混合三镜腔模型,建立了激光自混合用于变速测量的数学模型,提出了基于该模型的特征参量提取方法,该方法基于离散Chirp-Fourier变换理论。对激光自混合输出信号进行离散Chirp-Fourier变换,变换结果的主瓣坐标反映了物体运动的速度及加速度信息。最后,对该方法进行了仿真分析,在SNR=0 dB和SNR=7 dB的情况下,能较好地获得物体的速度和加速度信息。因此,仿真试验证明:该方法在较低信噪比的情况下仍能有效提取物体的速度及加速度信息。     

Interferometric measurement of the elongation of a pulsed diode laser

An interferometric technique was developed for detecting fast displacements of small areas in beam direction by less thanlambda/8. It utilizes a modified Michelson interferometer and a He-Ne laser light source. The technique was applied to measure the temporal and spatial evolution of the thermal mirror deformation of a GaAs-Ga1-xAlxAs single heterostructure laser diode. A small spot on the facet of the laser diode formed one mirror of the interferometer. The other mirror was moved linearly with time by applying a ramp voltage to a piezoelectric transducer. The diode was pulsed during this motion. The local elongation of the laser diode was evaluated from the interferometer output signal. The measured elongation of the active region at a time 1 μs after a 150-ns pulse with current density 48 000 A/cm²was between 4 and 20 nm, indicating a temperature rise of2-11degC. The smallest elongations detected were in the range of 0.5-1 nm. The measured values are in substantial agreement with theoretical expectations from thermal model calculations.     

波长调制光谱检测下限计算方法的研究

在基于波长调制光谱技术的大气痕量气体检测下限计算方法的研究中,全面准确地描述吸收信号及噪声的大小极为重要。为了探讨半导体二极管激光器在进行波长直接调制时伴随产生的残余振幅调制噪声对检测下限的影响,在理论推导中采用了一种同时考虑波长和振幅调制的二次谐波信号分析及提取方法,以二次谐波信号峰谷差值作为系统的检测信号,对可调谐二极管激光器吸收光谱检测系统的信噪比和检测下限进行了理论分析,取得了洛伦兹吸收线型条件下残余振幅调制噪声对系统信噪比和检测下限的影响的精确计算数据。结果表明,在吸收线的线宽较大的检测条件下,残余振幅调制噪声是影响检测下限的重要因素。     

Microwave/millimeter-wave frequency subcarrier lightwavemodulations based on self-sustained pulsation of laser diode

A method of subcarrier lightwave modulation based on the self-sustained pulsation (SSP) of laser diodes is presented. The tunable microwave/millimeter-wave frequency subcarrier is generated by the laser diode itself under proper DC biases. The subcarrier is frequency-modulated when the DC bias is superimposed with a small AC signal. No external modulation is needed. A theoretical analysis based on a double-section laser diode reveals that Hopf bifurcation is the origin of SSP. Theoretical calculations also show that the modulator has the potential of generating subcarriers up to 100 GHz by proper control of the device parameters V-channeled substrate inner-stripe (VSIS) GaAlAs laser diodes were used to generate 1-7-GHz SSP subcarriers. A preliminary subcarrier multiplexing (SCM) experiment demonstrated the transmission of 1-GHz modulation and video signals on a readily FM-modulated 6.3-GHz SSP subcarrier