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文章对由色散补偿光纤(DCF)、分布式拉曼放大的色散位移光纤(DSF)以及非线性光纤环镜(NOLM)构成的全光纤脉冲压缩器进行了理论分析和数值模拟.结果表明,光脉冲经DCF后可消除啁啾,为压缩提供有利条件;而经分布式拉曼放大的DSF后,脉冲得到了较大的压缩;最后再通过NOLM消基座.利用此压缩器可获得压缩率高且压缩效果好的光脉冲. 相似文献
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7.5-ps optical pulses generated from a gain-switched semiconductor laser at 2 GHz are successfully compressed down to 20 fs using a four-stage fiber soliton pulse compressor consisting of standard single-mode transmission, Er-doped, dispersion-decreasing, and dispersion-flattened fibers, respectively. We have experimentally confirmed that the soliton self-frequency shift plays an important role in obtaining such high compression in very short fibers, and also in minimizing the inherent undesirable pedestal component 相似文献
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Hao Dong Qiang Wang Hongzhi Sun N.K. Dutta 《Photonics Technology Letters, IEEE》2005,17(7):1396-1398
In this work, an optical short pulse generator is designed consisting of a pulse compressor and cascaded notch filter type repetition rate doublers. The performance characteristics such as pulsewidth and peak power as a function of design parameters are studied. The pulse compressor is optimized based on the simulation results. The 6-ps-wide pulses at 20-GHz repetition rate directly generated from mode-locked fiber laser are compressed to 1.25-ps-wide pulses. Using a set of polarization-maintaining fiber loop mirrors, the repetition rate is quadrupled and stable 1.45-ps-wide pulses at 80 GHz are achieved. 相似文献
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Complete characterization of ultrashort pulse sources at 1550 nm 总被引:1,自引:0,他引:1
Dudley J.M. Barry L.P. Harvey J.D. Thomson M.D. Thomsen B.C. Bollond P.G. Leonhardt R. 《Quantum Electronics, IEEE Journal of》1999,35(4):441-450
This paper reviews the use of frequency-resolved optical gating (FROG) to characterize mode-locked lasers producing ultrashort pulses suitable for high-capacity optical communications systems at wavelengths around 1550 nm, Second harmonic generation (SHG) FROG is used to characterize pulses from a passively mode-locked erbium-doped fiber laser, and both single-mode and dual-mode gain-switched semiconductor lasers. The compression of gain-switched pulses in dispersion compensating fiber is also studied using SHG-FROG, allowing optimal compression conditions to be determined without a priori assumptions about pulse characteristics. We also describe a fiber-based FROG geometry exploiting cross-phase modulation and show that it is ideally suited to pulse characterization at optical communications wavelengths. This technique has been used to characterize picosecond pulses with energy as low as 24 pJ, giving results in excellent agreement with SHG-FROG characterization, and without any temporal ambiguity in the retrieved pulse 相似文献
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The compression of higher order soliton pulses in dispersion decreasing fibers (DDF's) generates ultrashort fundamental soliton-like pulses accompanied by a broad low-intensity pedestal component. In this paper, we investigate the subsequent removal of the pedestal using a nonlinear optical fiber loop mirror (NOLM) to produce high-quality pulses. The influence of higher order effects such as stimulated Raman scattering and third-order fiber dispersion on the pedestal removal from ultrashort pulses are considered, and the effectiveness of using dispersion-flattened fiber within the loop is shown. The technique is experimentally demonstrated for 540-fs pulses generated by compression in DDF. In this case, high-quality pulses are produced by pedestal removal using a NOLM constructed from dispersion-shifted fiber 相似文献
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We report the first demonstration of pulse compression in optical fiber using linearly chirped Bragg gratings as quadratic compressors for pulses spectrally broadened by self-phase modulation. With the system investigated an initial 2 ps, bandwidth limited pulse is compressed by a factor of >10. The experimental results are found to be in good agreement with analytical and numerical calculations. Such a system allows high quality compression of pulses in optical fiber for the first time 相似文献
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A neodymium glass laser system capable of generating high-energy, ultrashort pulses at a convenient repetition rate is described. The effect of nonlinear frequency pulling on active mode locking is discussed. By minimizing the nonlinear frequency pulling, it is possible to routinely generate stable ~10-ps pulses at a 100-MHz repetition rate from the actively mode-locked oscillator. The regenerator amplifier increases the oscillator pulse energy to over 30 μJ at a 370-Hz repetition rate. Using intracavity self-phase modulation, the regenerative amplifier also broadens the pulse bandwidth to ~35 Å. By subsequent pulse compression while maintaining high energy, it is possible to produce 0.55-ps pulses with >10 μJ. An optical fiber pulse compressor further shortens the pulses to 30 fs (30 nJ), the shortest pulses ever generated at 1.054 μm from a neodymium laser system 相似文献
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采用全矢量有限元法和分步傅里叶法模拟计算了高非线性光子晶体光纤在近红外光谱区(特别是在850 nm)的飞秒脉冲孤子效应压缩,提出了一种新的反常群速度色散(2=-50.698 ps2/km)、小高阶色散和高非线性(=268.419 1 W-1/km)二氧化硅芯光子晶体光纤结构,建立了包含高阶色散和拉曼散射的非线性薛定谔方程,研究了高斯脉冲在此光纤中传输时,光纤长度和孤子阶数对脉冲压缩的影响,分析了光纤中2~5阶色散,研究表明:孤子阶数为8时,品质因子和压缩因子均达到最大,初始脉冲的峰值功率P0=3 357.8 W,压缩效果最好;优化光纤几何和光学参数,可以得到了高品质因数、小底座的超短光脉冲。 相似文献
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Barry L.P. Guignard P. Debeau J. Boittin R. Bernard M. 《Selected Areas in Communications, IEEE Journal on》1996,14(5):1030-1038
The authors demonstrate the use of time-division multiplexing (TDM) to realize a high capacity optical star network. The fundamental element of the demonstration network is a 10 ps, wavelength tunable, low jitter, pulse source. Electrical data is encoded onto three optical pulse trains, and the resultant low duty cycle optical data channels are multiplexed together using 25 ps fiber delay lines. This gives an overall network capacity of 40 Gb/s. A nonlinear optical loop mirror (NOLM) is used to carry out the demultiplexing at the station receiver. The channel to be switched out can be selected by adjusting the phase of the electrical signal used to generate the control pulses for the NOLM. By using external injection into a gain-switched distributed feedback (DFB) laser we are able to obtain very low jitter control pulses of 4-ps duration (RMS jitter <1 ps) after compression of the highly chirped gain switched pulses in a normal dispersive fiber. This enables us to achieve excellent eye openings for the three demultiplexed channels. The difficulty in obtaining complete switching of the signal pulses is presented. This is shown to be due to the deformation of the control pulse in the NOLM (caused by the soliton effect compression). The use of optical time-division multiplexing (OTDM) with all-optical switching devices is shown to be an excellent method to allow us to exploit as efficiently as possible the available fiber bandwidth, and to achieve very high bit-rate optical networks 相似文献
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综述了基于色散渐减光纤的绝热孤子压缩、高阶孤子压缩和非线性光纤环镜的光脉冲压缩的方法、原理及其进展,介绍了作者最近的研究成果,即采用色散渐减光纤构成的马赫--曾德尔干涉仪压缩光脉冲. 相似文献
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N.K. Berger B. Levit A. Bekker B. Fischer 《Photonics Technology Letters, IEEE》2004,16(8):1855-1857
Recently, a novel method for compression of periodic optical pulses based on a superposition of replicated and time-delayed original pulse trains was proposed. In this paper, we experimentally demonstrate that the phase shift of these replicas, as occurs in the temporal fractional Talbot effect, leads to compression without repetition-rate multiplication, which is inherent in the previous method. Simple and compact devices based on fiber Bragg gratings or fiber/or waveguide splitters/combiners, used for implementation of the present method can be considered as an equivalent of dispersive delay lines for periodic optical pulses. The proposed devices will also be available, for instance, for pulse generation, pulse-chirp compensation, temporal imaging, and real-time spectrum analysis for periodic optical pulses. 相似文献
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Ahmed K.A. Eggleton B.J. Hai-Feng Liu Krug P.A. Ouellette F. 《Photonics Technology Letters, IEEE》1995,7(2):158-160
Simultaneous pulse compression and mode selection of gain-switched pulses from a Fabry-Perot semiconductor laser are demonstrated using a chirped optical fiber Bragg grating, which has transformed initially chirped 60-ps pulses from an inexpensive multimode laser into a train of 12-ps single-mode pulses with a side-mode suppression ratio of 15.2 dB 相似文献
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The optically compressed pulses from a CW mode-locked Nd:YAG laser operating at 1.32 μm have been further compressed through a high-order soliton generation effect in a 40 m length of single-mode dispersion-shifted optical fiber. Two- and three-fold splitting of the soliton pulses have been demonstrated. Experimental compression factors and spectra forN = 3, 5, 7, 9, 11 , and 13 solitons have been shown to agree qualitatively with theory. In shorter fiber lengths pulses as short as 33 fs have been generated, corresponding to an over-all compression factor of X2700, the largest reported so far. 相似文献
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Schlager J.B. Yamabayashi Y. Franzen D.L. Juneau R.I. 《Photonics Technology Letters, IEEE》1989,1(9):264-266
Erbium fiber lasers are described that have cavity lengths of 20-5000 m and are mode-locked at the fundamental cavity frequency using an integrated-optic intensity modulator driven by a novel pulse generator. Resulting optical pulses at 1536 nm were recorded with a synchroscan streak camera and show durations of 10-80 ps with peak powers over 6 W. The shorter cavities yield nearly transform-limited pulses, which are narrowed by solitonlike compression to approximately 5 ps after propagation through an external 14 km fiber 相似文献
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A. Yu. Chamorovskiy S. A. Nikitov 《Journal of Communications Technology and Electronics》2013,58(9):879-890
Suspended-core microstructured optical fibers are employed in lasers that generate ultrashort pulses and supercontinuum generators. It is demonstrated that a femtosecond fiber laser based on the ytterbium-doped microstructured fiber generates pulses with a duration of 95 fs at a wavelength of 1045 nm and a mean power of 5 mW in the absence of additional compression. Supercontinuum is generated in tapered microstructured fibers with suspended core in the wavelength interval 400–1400 nm. Suspended-core micro-structured fibers may serve as promising elements for nonlinear optical devices due to specific waveguide characteristics, relative simplicity of manufacturing, and variable optical properties. 相似文献
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Patrice Tchofo Dinda Alexis Labruyere Kaliyaperumal Nakkeeran Julien Fatome Alain Brice Moubissi Stéphane Pitois Guy Millot 《电信纪事》2003,58(11-12):1785-1808
We present some theoretical and experimental results which suggest the possibility of constructing a non-empirical methodology of designing optical transmission systems with ultra high bit-rate per channel. Theoretically, we present an average dispersion decreasing densely dispersion-managed (A4dm) fiber system, which exhibits many advantages over the densely dispersion-managed fiber system, such as the possibility of transmitting chirp-free Gaussian pulses at 160 Gbit/s per channel over transoceanic distances, with a reduced energy and minimal intra-channel interaction. Experimentally we present generation of a 160-GHz picosecond pulse train at 1550 nm using multiple four-wave mixing temporal compression of an initial dual frequency beat signal in the anomalous-dispersion regime of a non-zero dispersion shifted fiber. A complete intensity and phase characterization of the pulse train by means of a frequency-resolved optical gating technique is achieved, showing generation of transform-limited pedestal-free Gaussian pulses. 相似文献
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M. Yousaf Hamza Noureen Akhtar Nadeem Sarwar Shiquan Yang 《Telecommunication Systems》2014,55(4):451-459
We present the results of tan-h pulse propagation through single mode fiber in dispersion dominant regime as well as in the simultaneous presence of fiber loss, group velocity dispersion and self-phase modulation. Both un-chirped/chirped cases have been considered. The pulse was propagated using split-step Fourier method based nonlinear Schrödinger equation. Results clearly show that in the absence of fiber nonlinearity, the pulse goes on broadening with the propagated distance. However, in the presence of the fiber nonlinearity, the pulse initially experiences compression and then undergoes broadening at a faster rate. As the value of sharpness parameter increases, the compression also increases. The results of compensation of group velocity dispersion using dispersion compensating fiber considering the setups of pre-, post- and the combination of pre- and post-compensations are also presented. These investigations provide a detailed study and deeper insight about how fiber responses to such type of optical pulses. 相似文献