大功率低阈值980nm单模AlGaInAs/AlGaAs量子阱激光器

To achieve low threshold current as well as high single mode output power,a graded index separate confinement heterostructure(GRIN-SCH)AlGaInAs/AlGaAs quantum well laser with an optimized ridge waveguide was fabricated.The threshold current was reduced to 8 mA.An output power of 76 mW was achieved at100 mA current at room temperature,with a slope efficiency of 0.83 W/A and a horizon divergent angle of 6.3.The maximum single mode output power of the device reached as high as 450 mW.     

低阈值电流、高量子效率脊形波导激光器

研制了低阈值电流、高量子效率670nm压缩应变单量子阱GaInP/AIGalnP脊形波导激光器。测量解理成的激光器条,腔长为300μm时,阈值电流为12．8mA,双面外部量子效率之和达到94．6％。     

小垂直发散角大光腔980nm单模InGaAs/GaAs/AlGaAs量子阱激光器

通过采用经过优化的新型大光腔结构,脊形波导980nm单模InGaAs/GaAs/AlGaAs多量子阱半导体激光器在保持大功率光输出的同时获得了较小的垂直发散角.结果表明波导中的光功率密度可以降低,获得了大于400mW、斜率效率0.89W/A的输出光功率,垂直方向远场发散角也降低到23°.     

小垂直发散角大光腔980nm单模InGaAs/GaAs/AlGaAs量子阱激光器

通过采用经过优化的新型大光腔结构,脊形波导980nm单模InGaAs/GaAs/AlGaAs多量子阱半导体激光器在保持大功率光输出的同时获得了较小的垂直发散角.结果表明波导中的光功率密度可以降低,获得了大于400mW、斜率效率0.89W/A的输出光功率,垂直方向远场发散角也降低到23°.     

单横模光子晶体微腔激光器的研究

对单横模激射的光子晶体垂直腔面发射激光器的设计具有指导作用。把单横模光子晶体光纤理论用于光子晶体微腔,分析有效归一化频率随晶格常数和填充比的变化关系;采用时域有限差分方法计算二维空气孔型三角结构光子晶体的完全带隙。利用上述计算结果,选取合适的光子晶体结构参数,实现单横模激射。从载流子数面密度和光子数面密度的速率方程出发,分析了光子晶体的引入对激光阈值的影响。     

具有一级光栅的980nm大功率宽条分布反馈激光器

为了达到较高的泵浦效率及波长稳定性,制备了980nm宽条形分布反馈半导体激光器。利用纳米压印技术制备了周期为148nm的一级内置光栅。器件发光条宽为90μm,腔长为2mm。在连续工作条件下,器件的最大输出功率达到1.2W以上,斜率效率为0.7W/A,中心波长随电流和温度的漂移系数分别降至0.19nm/A和0.064nm/K,波长锁定的温度范围达到50℃。     

High power and low optical feedback noise AlGaAs single quantum well lasers

GaAs-AlGaAs single quantum well self-aligned lasers have been developed for optical disc recording. The lasers emitting at 834 nm have realised low optical feedback noise as well as high output power. The lasers have shown less than -130 dB/Hz relative intensity noise at 3 mW, and stable 50 mW operation (over 500 hours at 50 degrees C ambient).<>     

CSP Al_xGa_(1-x)As/GaAs单模激光器

本文报道了CSP Al_xGa_(1-x)As单模激光器的性能及其制造技术.     

Al_xGa_(1-x)As/GaAsCSP可见光单模激光器

近0.78μm可见光单模激光器在光盘技术,包括视频盘、PCM声频盘和光盘存贮器、激光束高速打印、销售点(POS)终端等信息终端装置中有着广泛的应用前景。特别是打印机和小型光盘应用量大而广。另外,用近可见光单模LDs及其列阵作光源泵浦Nd:YAG激光器和1.06μm单模光纤放大器又是新近国内外十分热门的课题。因此,研制和生产可见光半导体单模激光器,有较大经济效益和发展前景。 本文报道用800℃下液相外延技术研制成稳定基横模、单纵模工作的Al_xGa_(1-x)As/GaAsCSP可见光(λ～779.0nm)单模LDs及其主要性能。     

具有高特征温度的808 nm大功率半导体激光器

研制出利用液相外延方法生长808 nm InGaAsP/GaAs分别限制单量子阱激光器,其室温连续输出功率达到4 W,室温工作的特征温度达到218 K.     

基于布拉格反射镜的单模太赫兹量子级联激光器

常规的分布式布拉格反射（DBR）半导体激光器中,增益区域所对应的自由谱间距应大于DBR高反射率带宽的1/2,以获得稳定的单模激射。该条件限制了DBR激光器的阈值和功率特性。文章首次提出并实现了基于DBR选模的太赫兹量子级联激光器（THz-QCL）,并突破了上述限制。作者所实现的THz-QCL采用脊波导结构,利用解理腔面和DBR反射镜构成谐振腔,利用有源区增益谱较窄的特点,通过调整DBR反射率谱使增益谱与DBR高反射带在频域中部分重叠,从而获得了单模激射的THz-QCL。该方案使得DBR高反射带显著宽于自由谱间距,即显著提高了激光器中增益区域的长度,从而降低阈值并提高功率特性。实验上,作者研制出增益区域长达3.6 mm的DBR激光器,单模激射的频率为2.7 THz,边模抑制比达到25 dB,该激光器的阈值和温度特性与相同材料制备的法布里-泊罗腔多模激光器相当。文章中的工作为实现高性能单模太赫兹量子级联激光器提供了新的研究思路。     

Passivation of the facets of 980 nm GaAs pump lasers by a pulsed UV laser-assisted technique

It is reported on the passivation of the mirror facets, opened in the air, of ridge waveguide InGaAs/GaAs/AlGaAs single quantum well (λ=980 nm) laser diodes. The passivation concept consists of two steps, namely, oxide removal by irradiation of the mirror facets with a pulsed KrF laser, immediately followed by the deposition of a thin silicon layer. The experimental arrangement (the process operation and the aging behavior-resistance to catastrophic optical damage) of the lasers thus treated are described. The structural modification of the laser facets, as probed by micro-Raman spectroscopy and Rutherford backscattering spectroscopy, and the calibration technique used to assess the rate of oxide removal are also presented.     

一种新型低功耗电流模式CMOS带隙基准设计

为了降低传统带隙基准源的功耗和面积,提出了一种新型基于电流模式高阶曲率修正的带隙基准电压源电路。通过改进的电流模式曲率校正方法实现高阶温度补偿,并且通过集电极电流差生成绝对温度成正比（PTAT）电流,而不是发射极面积差,因此所需电阻以及双极型晶体管（BJT）数量更少。采用标准0.35μm CMOS技术对提出电路进行了具体实现。测量结果显示,温度在-40～130°C之间时,电路温度系数为6.85 ppm/°C,且能产生508.5mV的基准电压。该带隙基准可在电源电压降至1.8 V的情况下工作,在100Hz时,测量所得的电路电源抑制为-65.2dB。在0.1-10 Hz频率范围内,噪声电压均方根输出为3.75 μV。相比其他类似电路,当供电电源为3.3V时,提出电路的整体静态电流消耗仅为9.8μA,面积仅为0.09 mm2。     

单模激光场与N个原子相互作用理论

本文用玻色算符的三维型哈密顿量描述单模激光场与Ｎ个两能级原子的相互作用。在原子系统处于低能态、光子数很大的初始条件下得到了作用系统的动力学变化规律。     

大功率小垂直发散角980nm量子阱激光器

提出了一种新型非对称宽耦合波导结构,通过理论计算优化了结构中n型波导层和限制层厚度,并采用低压金属有机化学气相沉积方法生长了设计的器件结构.测试了器件的光电特性,1200μm腔长器件的阈值电流为590 mA,斜率效率为0.96 w/A,最大输出功率达2000mW;当注入电流为0.6 A时,其远场发散角为16.1°(θ⊥)×10.2°(θ//).实验结果表明:新型非对称宽耦合波导结构能实现器件大功率输出,有效减小器件远场垂直发散角,改善器件光束质量.     

High output power single longitudinal mode graded index separateconfinement multiple quantum well InGaAs/InP distributed feedback (GRINSCH MQW DFB) lasers

A high continuous-wave (CW) output and high quantum efficiency of 1.5 μm-wavelength InGaAs/InP graded-index separate-confinement multiple-quantum-well DFB lasers were demonstrated. A threshold current of 45 mA with a maximum output power close to 100 mW and a quantum efficiency of 0.33 mW/mA was obtained. Single-frequency light output with power as high as 16 dBm (40 mW) was launched into a single-mode fiber     

InGaAsP/InP Buried‐Ridge Waveguide Laser with Improved Lateral Single‐Mode Property

A novel InGaAsP/InP buried‐ridg waveguide laser diode structure is proposed and demonstrated for use as a single‐mode laser. The lateral mode of the proposed device can be controlled by adjusting the composition and thickness of the InGaAsP layer grown over the active region. Stable single‐mode operation without kinks or beam‐steering is achieved successfully with lateral and transverse in the junction plane even for the device with the ridge width of 9 μm up to an injection current of 500 mA.     

波长632.8nm的He-Ne激光器在不同频差下的功率调谐曲线

激光纵模分裂技术能使双频激光器的频差从几十兆赫到几百兆赫,我们进行了一系列的实验来研究不同频差下激光器的光输出功率特性,实验结果表明,不论激光器充Ne²⁰还是Ne²²,也不管输出光的频差多大,随着腔长的调谐,o光和e光的功率变化方向是相反的.