共查询到20条相似文献,搜索用时 109 毫秒
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Chung W.H. Chan L.Y. Tam H.Y. Wai P.K.A. Demokan M.S. 《Photonics Technology Letters, IEEE》2002,14(7):920-922
Experimental results of a distributed feedback fiber laser injection locked to a Fabry-Perot laser diode are presented. By adjusting the injection power of the fiber laser to the Fabry-Perot laser, high quality laser output with a degree of polarization larger than 95% and sidemode suppression ratio higher than 45 dB was achieved. A 3.8-dB power penalty improvement was also demonstrated in a 41-km 10-Gb/s transmission experiment 相似文献
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Liu P.-L. Fencil L. Ko J.-S. Kaminow I. Lee T.-P. Burrus C. 《Quantum Electronics, IEEE Journal of》1983,19(9):1348-1351
We experimentally show that the statistical distribution of the light output from an injection laser can be adequately described by the superposition of a coherent electric field and narrow-band Gaussian noise. A technique for measuring these fluctuations in the time domain with a resolution of 120 ps is described. The results for several InGaAsP lasers show that intensity fluctuations in an injection laser are rather large, so that the probability of finding the output below 50 percent of the average power in a 120 ps time interval can be as high as 10-5. 相似文献
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多普勒测风激光雷达以其高分辨率、高精度、大探测范围、能提供三维风场信息的能力,吸引了多国学者的关注,并投入了大量的人力、物力进行研究。所研究的多普勒测风激光雷达采用种子注入的方式获得单纵模、窄线宽、高功率的激光输出。激光器中心频率的缓慢漂移、环境噪音、激光棒温度变化或者振动干扰都有可能导致激光器种子光的注入不成功,出射激光光谱由注入成功时的单纵模输出变为多纵模输出。激光单纵模输出时线宽约为200 MHz,而多纵模时激光线宽很宽。而种子注入不成功时所出射的多纵模激光脉冲将导致瑞利后向散射谱变宽,会增加风速测量误差。该脉冲筛选电路在数据采集环节实现对多纵模激光脉冲的筛选,有效降低了风速测量误差,提高测风准确度。 相似文献
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为了制备大功率、单横模输出的量子点激光器,对有源多模干涉波导结构进行了研究。通过优化器件结构设计,采用1×1型有源多模干涉波导结构,以均匀多层InAs/InGaAs/GaAs量子点材料作为有源区,制备了1.3μm波段的有源多模干涉结构量子点激光器。连续电流注入条件下的测试结果表明,与传统的均匀波导结构器件相比,有源多模干涉结构器件具有更低的串联电阻和更好的散热性能;在连续电流为0.5A的小注入情况下,器件的输出功率可达114mW、中心波长为1332nm。结果表明,有源多模干涉结构器件是制备大功率、单横模输出光发射器件的一种有效的器件结构。 相似文献
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注入锁定法布里-珀罗激光器的单模工作特性 总被引:1,自引:1,他引:0
使用分布式反馈(DFB)激光器对法布里-珀罗(F-P)激光器进行单模注入锁定.通过改变F-P激光器的偏置电流,DFB激光器的输出功率以及两激光器间的波长失谐量,对注入锁定F-P激光器的光谱特性、功率特性以及频率响应特性进行实验分析.找出影响注入锁定F-P激光器稳定性的因素,并测量注入锁定F-P激光器的稳定锁定区;通过优化注人条件实现F-P激光器的高边模抑制比(SMSR)输出,最高可达55 dB;通过与自由运转F-P激光器比较,发现注入锁定可以明显抑制半导体激光器在高频调制下光谱的展宽.注入锁定后F-P激光器的3 dB调制带宽接近14 GHz.实验结果表明,通过合理设计光注入条件,注入锁定技术可以明显改善F-P激光器的光谱特性以及高频响应特性,并在高速光纤通信领域中得到广泛应用. 相似文献
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Felix C.L. Bewley W.W. Vurgaftman I. Meyer J.R. Zhang D. Lin C.-H. Yang R.Q. Pei S.S. 《Photonics Technology Letters, IEEE》1997,9(11):1433-1435
A 22-stage interband cascade laser with a “W” active region for enhanced gain has exhibited lasing at λ=3.0 μm. Threshold current densities are lower than the best reported intersubband quantum cascade laser results at all T up to the maximum lasing temperature of 225 K. At 100 K, output powers up to 430 mW are observed, and the slope of 274 mW/A per facet for high injection levels corresponds to a quantum efficiency of 1.3 photons emitted for every injected electron 相似文献
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The mode and the output properties of an asymmetric λ/4-shifted DFB (distributed-feedback) laser with a distributed injection current density along the cavity are investigated theoretically and experimentally. Coupled wave equations that describe the longitudinal spatial hole-burning phenomenon due to both distributions of a stimulated recombination carrier density and an injection current density are developed. The calculations show that an appropriate distribution of the injection current similar to the intensity profile can be effectively suppress the longitudinal spatial hole-burning effect from the aspect of threshold gai difference Δαth. A 1.55-μm InGaAsP/InP asymmetric λ/4-shifted DFB laser was fabricated with three divided electrodes. Improvement of the linearity of the output characteristics, decrease of threshold current, stability of the single-mode property, and narrowing of the spectral linewidth by injection current and distribution along the cavity were observed 相似文献
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Tittel F. Marowsky G. Nighan W. Yunping Zhu Sauerbrey R. Wilson W. 《Quantum Electronics, IEEE Journal of》1986,22(11):2168-2173
Efficient, ultra-narrow spectral output from an electron-beam excited XeF(C rightarrow A ) laser medium has been achieved by injection-controlled tuning. Using a pulsed dye laser as the injection source, amplified output pulses tunable between 435 and 535 nm and having a spectral width of 0.001 nm were obtained. For a 482.5 nm injection wavelength that is well matched to the XeF(C rightarrow A ) gain maximum, output energy density and intrinsic efficiency values of approximately 8 J/l and 6 percent were achieved. 相似文献
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A pulse output energy of 170 J has been achieved from an XeF(C→A) laser system, pumped by a pair of counterpropagating, three-meter-long electron beams. This represents a record for all types of pumping, for this excimer system. Energy was extracted from a volume of ~100 L, using a free-running stable oscillator. No evidence of laser oscillations on the competing XeF(B→X) transition was observed. Within the extraction volume the laser gas was pumped at a rate of 140 kW/cm3 (time average value), for a period of 1.7 μs. The optical cavity was folded, giving a gain length of 6 m. The optical pulse duration was 0.8 μs (full width at half maximum), and the observed flux buildup time of ~1 μs was consistent with modeling and a measurement of the net gain. The specific output energy was 1.7 J/L which is comparable to that achieved in previous, small scale experiments at somewhat higher pump rate. The results confirm the volumetric scalability of the electron beam pumped XeF(C→A) laser system to high output energy per pulse, and the feasibility of operating this system at a low electron beam pump rate which relaxes constraints on the design of the electron gun and pulse power subsystems in a high output energy device. Means for extending the laser pulse duration and increasing the output energy of the specific test device are discussed. An output energy of ~1000 J is projected for an optimized gas cell width, for full size resonator mirrors, and with injection 相似文献
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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%。 相似文献
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Jai-Ming Liu Ying-Chin Chen 《Quantum Electronics, IEEE Journal of》1985,21(4):298-306
The operations of a complete set of optical AND, NAND, OR, and NOR gates and clocked opticalS-R, D, J-K, andT flip-flops are demonstrated, based on direct polarization switching and polarization bistability, which we have recently observed in InGaAsP/InP semiconductor lasers. By operating the laser in the direct-polarization-switchable mode, the output of the laser can be directly switched between the TM00 and TE00 modes with high extinction ratios by changing the injection-current level, and optical logic gates are constructed with two optoelectronic switches or photodetectors. In the polarization-bistable mode, the laser exhibits controllable hysteresis loops in the polarization-resolved power versus current characteristics. When the laser is biased in the middle of hysteresis loop, the light output can be switched between the two polarization states by injection of short electrical or optical pulses, and clocked optical flip-flops are constructed with a few optoelectronic switches and/or photodetectors. The 1 and 0 states of these devices are defined through polarization changes of the laser and direct complement functions are obtainable from the TE and TM output signals from the same laser. Switching of the polarization-bistable lasers with fast-rising current pulses has an instrument-limited mode-switching time on the order of 1 ns. With fast optoelectronic switches and/or fast photodetectors, the overall switching speed of the logic gates and flip-flops is limited by the polarization-bistable laser to < 1 ns. We have demonstrated the operations of these devices using optical signals generated by semiconductor lasers. The proposed schemes of our devices are compatible with monolithic integration based on current fabrication technology and are applicable to other types of bistable semiconductor lasers. 相似文献
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The mutual injection-locking properties of a coupled pair of multiple-quantum-well distributed-feedback lasers with grating output couplers were investigated experimentally and theoretically. When the mutual injection locking occurred, the output of one laser decreased while that of the other increased. The locking curve was asymmetric, and a stable and an unstable locking region existed. From the theoretical analysis, it was found that the phase delay with which the electric field emitted from each laser to the other laser significantly influences the locking characteristics. The increase and decrease of the locked output power are caused by the phase delay. It is also shown that the laser which receives the larger optical injection behaves like a slave laser and the laser which has less optical injection behaves like a master laser, and the shape of the locking curve is determined by the balance between the α parameter and the thermal resistance 相似文献
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Hamada N. Sauerbrey R. Wilson W.L. Jr. Tittel F.K. Nighan W.L. 《Quantum Electronics, IEEE Journal of》1988,24(8):1571-1578
Characteristics of an injection-controlled electron-beam pumped XeF(C →A ) laser are investigated with emphasis on efficient wideband tuning and scaling issues. Using a quasi-CW dye laser as an injection source, data are obtained that describe the laser characteristics over a wide parameter range. A high-Z electron-beam backscattering reflector inside the laser reaction cell improved the electron-beam energy deposition by 40%, resulting in an increase of the amplified laser output by more than a factor of four. Efficient and continuous wavelength tuning between 470 and 500 nm is achieved with an output energy density of ~1 J/l, and an intrinsic efficiency of ~1% throughout the entire tuning region 相似文献
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We report the results of an experimental study to determine the minimum required injected power to control the output frequency of a TEA CO2 laser. A CW CO2 waveguide laser was used as the injection oscillator. Both the power and the frequency of the injected radiation were varied, while the TEA reasonator cavity length was adjusted to match the frequency of the injected signal. Single-longitudinal mode (SLM) TEA laser radiation was produced for injected power levels which are several orders of magnitude below those previously reported. The ratio of SLM output power to injection power exceeded 1012at the lowest levels of injected intensity. 相似文献
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面向芯片原子钟(Chip Scale Atomic Clock,CSAC)的垂直腔面发射激光器(Vertical Cavity Surface-Emitting Laser,VCSEL)通过微波调制产生具有特定光频差的相干激光,与原子作用后的跃迁谱线频率作为参考标准,最终可获取高精度的频率信号。因此,垂直腔面发射激光器在芯片原子钟系统中至关重要。介绍了VCSEL激光器的内调制原理,搭建了其内调制特性实验测试平台,开展了激光器对射频调制响应特性研究,记录了激光器边带信号随着注入电流和射频输出功率的变化情况,并分析了射频调制对激光器边带信号的影响特性以及Bogatov现象引起的边带不对称现象。实验结果显示:当射频信号频率为3.41734 GHz,注入电流为1.2 mA,射频输出功率为3.5 dBm时,可获得优化的高频调制光谱,为芯片原子钟提供优质的光源。 相似文献
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The output state of a broad-area diode (BAD) laser with phase conjugate feedback (PCF) from Rh:BaTiO3 crystal is compared to the same diode laser with conventional optical feedback from a plane mirror. A number of distinct output states, including low frequency fluctuations, are observed for each feedback type. Stable single spectral mode output is achieved with phase conjugate feedback above an injection current dependent critical level (~20%). Conventional optical feedback from a plane mirror does not induce single-mode output at any feedback level 相似文献