应力对M-Z型InP/InGaAsP-EAM偏振

采用Agilent 81910A光子全参量测试仪,首次实验研究了InP/In1－xGaxAs1－yPy-MQW（Multiple-Quantum-Well,MQW）材料与衬底间因应力而产生的M-Z型光调制器的PDL影响以及由此引起的由差分群时延(Differential Group Delay,DGD)表征的偏振模色散(Polarization Mode Dispersion,PMD).研究结果表明,半导体MQW光调制器的PDL与DGD是一致的.因此在半导体光器件的制作过程中,应尽可能地减小衬底与波导芯层之间的因残存应力的存在造成对光器件的高速性能的不利影响.     

Simulation of Birefringence and Absorption in InGaAs-GaAs Multiple Quantum Well Acoustooptic Modulators Operating Near 980 nm

This paper presents the simulation of surface acoustic wave (SAW)-induced absorption coefficient and refractive index change in InGaAs-GaAs multiple quantum well (MQW) structures operating near 980 nm. The exciton problem is solved in two dimensional momentum space to include the non-axial effect due to strain induced valance band mixing and nonparabolicity. The optical absorption coefficient and refractive index changes near the band gap in the MQWs are calculated as a function of SAW power.     

Relative intensity noise of mode-locked fiber grating external cavity semiconductor lasers

The noise of hybrid soliton pulse source (HSPS) with linearly chirped Gaussian apodized fiber Bragg grating is analyzed by couple-mode equations including spontaneous emission noise when the HSPS is mode-locked. Relative intensity noise is calculated using numerical solutions of these equations. It is shown that transform limited pulses are generated over a wide tuning range around the fundamental mode-locking frequency with low spontaneous noise. However, a high noise level affects the operation of device, and therefore transform-limited pulses are not obtainable over a wide tuning range. It is also shown that noise is extremely sensitive to the RF and DC currents, linewidth enhancement factor, gain saturation parameter and spontaneous coupling factor.     

金属有机化学气相沉积外延技术生长GaN基半导体发光二极管和激光二极管(Ⅰ)

文章评论性地介绍了金属有机化学气相外延技术（MOCVD）生长氮化物半导体GaN和InGaN以及激子局域化效应、量子束缚斯塔克效应对它们的光学性能的影响，详细比较了这两种效应对GaN基半导体发光二极管和激光二极管特性的影响，特别是量子束缚斯塔克效应以显著不同的方式影响着发光二极管和激光二极管的性能；文章还讨论了在A面蓝宝石衬底上生长GaN的情况．     

GaAs/GaAlAs多量子阱反射型光调制器及自电光效应器件

采用分子束外延技术生长含有大周期数的GaAs/GaAlAs多量子阶(MQW)及分布布喇格反射器(DBR)的PIN结构器件。研究了量子限制斯塔克效应(QCSE),分布布喇格反射及非对称腔模(ASFP)效应对光的反射调制作用及这三种效应的兼容性对光调制及逻辑器件的重要影响。给出我们研制的反射型光调制器及自电光效应器件的实验结果。对于常通型及常闭型调制器,其两态衬比度可达10dB.所研制的SEED器件,其导通光能耗低于10fJ/(μm)²,实现其光学双稳态及R-S光触发器工作。     

线性分段折射率分布多量子阱波导色散关系的精确分析

本文从标量Helmholtz方程出发,采用转移矩阵技术,求出了线性分段折射率分布多量子阶波导TE模色散关系的精确解,数值计算结果显示出该波导的色散特性以及与波导结构的关系,为实际制作该量子阶波导进行参数选择提供了理论依据。     

Characterization of [ZnO]m[ZnMgO]n multiple quantum wells grown by molecular beam epitaxy

Thermal stability of single-crystalline [ZnO]_m[Zn_0.7Mg_0.3O]_n multiple quantum wells (MQWs) grown on a-plane sapphire substrates by plasma-assisted molecular beam epitaxy is reported. X-ray diffraction analysis revealed that these MQWs were grown as designed with a fixed Zn_0.7Mg_0.3O barrier width of and a series of ZnO well widths of . Cathodoluminescence spectra from these MQWs consisted of two major peaks; one was the emission from the bound excitons in Zn_0.7Mg_0.3O barrier layers, and the other was that from the confined excitons in ZnO well layers. These structural and optical properties were found to be dramatically changed by the ex situ annealing treatments over 700 °C. These changes were presumably due to the onset of phase separation of the Zn_0.7Mg_0.3O barrier layers with pronounced Mg diffusion toward the ZnO wells.     

超薄溶液LPE技术生长GaInAsP/InP超晶格的理论与实验

本文由有限厚度溶液及自由表面浓度和恒定表面浓度二种模型出发对LPE生长动力学过程进行了理论分析,并导出了实现薄层生长的参数控制条件,根据这一条件用LPE技术实际生长了GaInAsP/InP超晶格,570℃下用突冷法及被压缩到200μm～500μm的薄层溶液在0.2s的驻留时间内分别重复长出了5nm(Ga0.40In0.60As0.89P0.11)和10nm(InP)的超晶格,证明了用重复推拉舟的LPE系统在一定的参数条件下可以生长MQW结构.     

用直接模拟法分析量子阱半导体激光器瞬态响应

根据光增益与载流子密度的对数关系 ,通过适应于多量子阱激光器的速率方程的直接模拟分析 ,得到了注入电流、阱数和腔长对多量子阱激光器的激射阈值、开关延迟时间、弛豫振荡频率和光输出等参量之间的依赖关系 .运用相图确立了在瞬态过程中 ,载流子数密度和光子数密度之间的转化过程 .从而为改善量子阱激光器的高频调制特性以及优化设计器件结构参数提供了理论依据     

Self-aligned Coupled Waveguide Distributed Bragg Reflector Lasers

A novel self-aligned coupled waveguide (SACW) multi-quantum-well (MQW) distributed Bragg reflector (DBR) laser is proposed and demonstrated for the first time. By selectively removing the MQW layer and leaving the low SCH/SACW layer the Bragg grating is partially formed on this layer. By optimizing the thickness of the low SCH/SACW layer, a～80% coupling efficiency between the MQW gain region and the passive region are obtained. The typical threshold current of the SACW DBR laser is 39 mA, the slope efficiency can reach to 0.2 mW/mA and the output power is more than 20 mW with a more than 30dB side mode suppression ratio.