共查询到20条相似文献,搜索用时 63 毫秒
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Wavelength characteristics and the wavelength tunability of the fiber loop mirror constructed by a fused taper coupler are studied for elongation and twisting. The difference between the reflected and the transmitted wavelengths decreases exponentially with the number of minimal transmissions of the monitored light during fiber mirror fabrication. The fiber loop mirror twisted the constituent coupler can be realized as a fiber coupler and an equivalent waveplate for a theoretical study. The measured spectrum transmission agrees well with the theory. The reflected and the transmitted wavelengths can be tuned by twisting fiber mirrors without significant degradation. The wavelength change due to twisting is reversible and repeatable 相似文献
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Shubochkin R.L. Kozlov V.A. Carter A.L.G. Morse T.F. 《Photonics Technology Letters, IEEE》1998,10(7):944-945
We demonstrate a tunable thulium-doped fiber ring laser wherein a single fused coupler acts simultaneously as the wavelength-division multiplexing for pump radiation, a lasing wavelength selective element, and output mirror. Temperature tuning of up to 2 nm/°C over a range of 40 nm and polarization tuning of over 100 nm within the spectral range from 1810 to 1930 nm have been obtained 相似文献
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Jianliang Yang Kejiang Zhou Yunqi Liu Swee Chuan Tjin 《Journal of Infrared, Millimeter and Terahertz Waves》2002,23(6):891-897
A photonics true-time-delay system for phased array beamforming using a chirped grating-based time-delay element and a novel multiwavelength erbium-doped fiber ring laser source employing a Sagnac filtering mirror is proposed. The Sagnac filtering mirror consists of a polarization maintaining directional coupler and two pieces of polarization maintaining fibers. The lasing wavelength and number are determined by properly adjusting the polarization controller within the unidirectional ring cavity and are very stable. A chirped-grating-based true-time-delay system using the proposed laser source is constructed and demonstrated experimentally. 相似文献
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Douay M. Feng T. Bernage P. Niay P. Delevaque E. Georges T. 《Photonics Technology Letters, IEEE》1992,4(8):844-846
The spectra of Nd3+- and Pr3+-doped fibre lasers utilizing an intracore Bragg grating reflector written at 1.08-μm Bragg wavelength and a dichroic mirror for cavity feedback have been investigated under 0.6-GHz resolution. Two oscillating frequencies corresponding to two orthogonal linear polarization states of laser emission were observed. The frequencies and orientations of the two linearly polarized emissions could be changed by varying the fiber birefringence with an inline polarization controller. A phenomenological model is proposed to explain the experimental results 相似文献
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熔锥平行排列3×3单模光纤耦合器的研究 总被引:12,自引:0,他引:12
平行排列 3× 3单模光纤耦合器在光开关、光缓存器、光谐振腔、光滤波器等方面有很重要的应用 ,偏振态的演化和波长特性是耦合器应用中的关键问题。利用模耦合理论对平行排列 3× 3单模光纤耦合器的输出性能进行了详细分析 ,得出了光纤引线对耦合器的输出偏振态演化起主要作用 ,而耦合区的影响则比较小 ;通过理论推导模耦合系数 ,分析了耦合器的分光比随波长的变化关系 ,得出了输出分光比比较稳定的耦合器所需要的合适芯间距(对于我们研制的为 12 .5 μm)。并采用可移动火焰实际研制出了具有长耦合区的平行排列 3× 3单模光纤耦合器 ,测试表明输入光波长在 1 5 0 0~ 1 5 75 μm范围内变化时 ,耦合器的输出分光比变化不大 ,理论与实验结果基本相符 相似文献
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为了研究基于半导体可饱和吸收镜的被动锁模光纤激光器的输出特性,采用1480nm的半导体激光器作为抽运源,利用掺铒光纤作为增益介质,以及光纤环行器、偏振控制器、波分复用器和耦合器等构成了环形腔结构的被动锁模光纤激光器。实验中获得了峰值波长1586nm、光谱宽度4.8nm、重复频率11.2MHz、最大平均输出功率8.4mW的稳定锁模激光脉冲输出。结果表明,调整光纤偏振控制器会使光纤激光器输出脉冲的时域波形略微发生变化,在实际应用中需要注意偏振态变化对锁模光纤激光器输出脉冲时域特性的影响。这一结果对于半导体可饱和吸收镜在被动锁模光纤激光器中的应用及其特性具有一定帮助。 相似文献
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In this paper, we demonstrate a novel multiwavelength L-band Brillouin-erbium fiber laser utilizing nonlinear amplifying loop mirror. The erbium-doped fiber section in the fiber loop mirror provides efficient amplification of Brillouin pump (BP) to generate the stimulated Brillouin scattering in the single-mode fiber coil. The laser structure can achieve symmetry breaking of the loop without requirements to an asymmetric coupler or polarization controller. The proposed fiber laser has a low threshold power of about 10 mW to create the first Brillouin-Stokes signal. The maximum number of 27 Stokes signals with a spacing of 0.089 nm is achieved by setting the BP wavelength at 1604 nm and its BP power is set at 2.2 mW. 相似文献
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Guanshi Qin Shenghong Huang Yan Feng A. Shirakawa K.-I. Ueda 《Photonics Technology Letters, IEEE》2005,17(9):1818-1820
In this letter, we report on a multiple-wavelength up-conversion laser in Tm/sup 3+/-doped ZrF/sub 4/--BaF/sub 2/--LaF/sub 3/--AlF/sub 3/--NaF glass fiber pumped by an 1120-nm fiber laser. Single-wavelength, two-wavelength, and three-wavelength up-conversion lasers can be obtained by adjusting the distance between the coupler mirror and the fiber end, which is attributed to the frequency-filter effect in the etalon composed of the coupler mirror and the fiber end. The effects of the pump power on the performance of dual-wavelength laser were also discussed. 相似文献
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介绍了一台a轴偏振的1 339 nm Nd:YAP脉冲激光器.通过分析Nd:YAP晶体的能级跃迁和光谱特性,采用偏振片抑制平行于晶体C轴偏振的激光振荡,并通过设计输出耦合镜的透过率抑制晶体a轴偏振的1 064 nm强线的振荡,成功实现a偏振的1 339 nm单一谱线脉冲激光输出.当输入电能量达到75 J时,激光输出能量为0.31 J,电-光转换效率为0.4%,斜率效率为0.52%,激光输出能量不稳定度≤±5%,激光阈值能量为14.5 J,输出脉冲激光的中心波长在1 339.2 nm. 相似文献
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WANG Ke-xin WANG Ting-yun PANG Fu-fei 《光电子快报》2007,3(1):14-17
Optical amplifiers are the key parts in many fiber-optic transmission systems such as fiber CATV network, subscribe access network and some military fields. Amplifying fiber i the core part in an optical amplifier, and till now most ampli fying fibers in … 相似文献
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Theoretical and experimental results are described for a new optical coupler which consists of two laser diodes, two GRIN spherical rod lenses, a polarizing filter, and a single-mode fiber, and which employs laser diode polarization characteristics for an optical submarine transmission laser redundancy system. This optical coupler has two channels at 1.3 μm wavelength. Optical coupler loss values, which include coupling loss, polarization loss, and assembly loss, are 4.9 dB for one laser diode and 5.2 dB for another laser diode. Such loss values are almost the same as the conventional laser diode module loss for a single-mode fiber. This paper describes in detail a laser redundancy system in an optical submarine transmission system, structure and characteristics of an optical coupler, and experimental results on a high bit rate long-haul transmission system using the proposed optical coupler. 相似文献
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Electrooptic tuning of a fiber ring semiconductor laser 总被引:1,自引:0,他引:1
This letter reports recent results obtained in the area of wavelength tuning of semiconductor lasers. The laser is constructed from an InGaAsP 1300-nm semiconductor optical travelling-wave amplifier. The cavity consists of a fiber ring resonator using a low fiber coupler as the output mirror. The intra-cavity electrooptic tuner works as a one-stage Lyot filter and allows wavelength tuning over a spectral range of 20 nm with a tuning rate of 0.05 nm V-1. This is one of the best results reported using electrooptic birefringent tuning systems 相似文献
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Schafer K. Baumann I. Sohler W. Suche H. Westenhofer S. 《Quantum Electronics, IEEE Journal of》1997,33(10):1636-1641
Design, fabrication, and properties of an acoustooptically tunable Ti:Er:LiNbO3 waveguide laser of up to 31-nm tuning range in the wavelength band 1530 nm<λ<1575 nm are discussed. The laser cavity is formed by an Au mirror and a dielectric mirror as output coupler, both vacuum-deposited on the polished waveguide endfaces. As tunable intracavity wavelength filter with zero frequency shift, two monolithically integrated single-stage acoustooptical TE-TM-mode converters are used together with two polarization splitters operated as TE- and TM-pass polarizers, respectively. The minimum threshold of about 54 mW (coupled) pump power is obtained at λ≈1561-nm emission wavelength for diode laser pumping at λp≈1480 nm. With about 110-mW coupled pump power, up to 320-μW output power is achieved; the emission linewidth is 0.3 nm 相似文献
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为了得到掺铒光纤环形激光器的激光运行波长与掺铒光纤长度和耦合比之间对应关系,基于3能级的速率方程采用解析方法进行了理论分析,并通过实验给予验证,分别取得了激光运行波长随掺铒光纤长度和耦合器耦合比变化的数据。结果表明,随着光纤长度的增加,激光的输出波长往长波方向移动,输出波长为1563nm 时输出功率最大,掺铒光纤最佳长度大约为11.5m,耦合比越大,激光的输出波长越短。这一结果对改变耦合比进行光纤激光器激光波长调谐的设计有很大帮助。 相似文献