厚度偏差对VCSEL的反射谱和反射相移的影响

采用光学传输矩阵方法分析了厚度偏差对VCSEL的反射谱和反射相移产生的影响。结果表明,反射镜和VCSEL中各层厚度的偏大,将使反射镜的中心波长以及VCSEL的模式波长向长波方向移动,而反射镜和VCSEL中各层厚度的偏小,将使反射镜的中心波长以及VCSEL的模式波长向短波方向移动。将键合界面离有源区稍微远一些,有利于减小其厚度偏差对VCSEL的模式波长的影响。     

双色量子阱红外探测器顶部光子晶体耦合层的设计优化

采用三维时域有限差分算法(3D-FDTD)对GaAs/AlGaAs量子阱红外探测器(QWIP)的顶部光子晶体光输入耦合层结构的电磁场分布进行了仿真分析,得到了多种不同周期、占空比、深度的二维光子晶体结构耦合效率及电磁场分布.探索了一种双色探测器的光子晶体光输入耦合层结构的设计思路,使之可对中波/长波或长波双色8/12 μm同时提供较高的耦合效率. 关键词： 红外探测器 量子阱 光子晶体     

慢光在光子晶体弯折波导中的高透射传播

研究了慢光模式在SOI(silicon-on-insulator)材料光子晶体线缺陷弯折波导中的传输特性. 通过优化波导弯折处的结构参数,慢光模式在光子晶体60°与120°弯折波导中的透射率提高10倍以上,归一化透射率分别达到80%和60%以上. 为了进一步减慢光速,设计了新颖的高Q值耦合腔弯折波导结构,在归一化透射率达到75%的基础上,光波群速度低至c/170(c为真空光速). 研究结果对于增强光子晶体的慢光效应,提高光子晶体慢光器件的微型化和集成化都有一定的积 关键词： 光子晶体 慢光 弯折波导 透射率     

Design of a compact polarization beam splitter based on a deformed photonic crystal directional coupler

In this paper a compact polarization beam splitter based on a deformed photonic crystal directional coupler is designed and simulated. The transverse-electric （TE） guided mode and transverse-magnetic （TM） guided mode are split due to different guiding mechanisms. The effect of the shape deformation of the air holes on the coupler is studied. It discovered that the coupling strength of the coupled waveguldes is strongly enhanced by introducing elliptical airholes, which reduce the device length to less than 18.Sttm. A finite-difference tlme-domain simulation is performed to evaluate the performance of the device, and the extinction ratios for both TE and TM polarized light are higher than 20 dB.     

10—14 μm同时响应的双色量子阱红外探测器

实现截止波长为11.8和14.5 μm双色同时响应的量子阱红外探测器,可以同时工作在8—12 μm大气窗口和甚长波波段.在77 K下测量到很强的光电流谱.器件结构采取了较为简洁的设计,通过适当增大量子阱结构中势阱的宽度和选择合适的掺杂浓度,在同一偏压下实现了对两个波长的同时响应.两个光响应峰分别为基态到第五激发态和基态到第一激发态的跃迁吸收. 关键词： 量子阱红外探测器 双色 同时响应     

High power AlGaInP laser diodes with zinc-diffused window mirror structure

The technology of zinc-diffusion to improve catastrophic optical damage (COD) threshold of compressively strained GaInP/AlGaInP quantum well laser diodes has been introduced. After zinc-diffusion, about 20 μm-long region at each facet of laser diode has been formed to serve as the window of the lasing light. As a result, the COD threshold has been significantly improved due to the enlargement of bandgap by the zinc-diffusion induced quantum well intermixing, compared with that of the conventional non-window structure. 40-mW continuous wave output power with the fundamental transverse mode has been realized under room temperature for the 3.5μm-wide ridge waveguide diode. The operation current is 84 mA and the slope efficiency is 0.74 W/A at 40 mW. The lasing wavelength is 656 nm.     

Influence of GaAsP Insertion Layers on Performance of InGaAsP/InGaP/A1GaAs Quantum-Well Laser

We report on the use of very thin GaAsP insertion layers to improve the performance of an In GaAsP/InGaP/AIGaAs single quantum-well laser structure grown by metal organic chemical vapour deposition. Compared to the noninsertion structure, the full width at half maximum of photoluminescence spectrum of the insertion structure measured at room temperature is decreased from 47 to 38 nm indicating sharper interfaces. X-ray diffraction shows that the GaAsP insertion layers between AIGaAs and InGaP compensates for the compressive strain to improve the total interface. The laser performance of the insertion structure is significantly improved as compared with the counterpart without the insertion layers. The threshold current is decreased from 560 to 450 mA while the slope efficiency is increased from 0.61 to 0.7W/A and the output power is increased from 370 to 940mW. The slope efficiency improved is very high for the devices without coated facets. The improved laser performance is attributed to the suppression of indium carry-over due to the use of the GaAsP insertion layers.     

条形半导体激光器光束质量因子M2的理论计算

通过一个二维半矢量模型求得纯折射率导引脊形波导和掩埋波导这两种常见平面条形半导体激光器波导结构的模式光场分布，现通过描述光束传播的非傍轴矢量二阶矩，通过平面波谱的方法获得激光器出射光束在横向和侧向上的束腰、远场发散角和M^2因子。讨论了波导结构参量变化对M^2因子的影响，并对两种波导结构光束的性质与波导参量的关系进行了比较。     

微小孔径激光器的工艺及器件功率和寿命特性分析

在650nm波长半导体激光器的基础上制造出了高输出功率的微小孔径激光器.驱动电流为25mA时， 输出功率达到0.4mW，最大功率可达１mW以上.叙述了微小孔径激光器的特殊的制造工艺，并分析了器件可能的失效机理. 关键词： 近场光学 微小孔径激光器 半导体激光器 失效分析     

1.8—4.2K GaAs_(1-x)P_x注N~+,注Zn~+光荧光谱

本文研究了1.8—4.2K下离子注N,注Zn GaAs_(1-x)P_x样品的光致发光行为。实验结果表明由N-Zn跃迁完全转变到N束缚激子复合的x值依赖N,Zn的浓度。 利用Campbell局域化模型计算了N-Zn跃迁与N束缚激子复合的几率比。这一几率比是组分x和N-Zn浓度的函数。 在1.8K,在同一样品上我们清晰地观测到对应N-Zn跃迁与N束缚激子复合的光谱。