共查询到20条相似文献,搜索用时 140 毫秒
1.
2.
3.
4.
为了获得高功率优质的超短脉冲光源,利用色散渐增光纤产生的强线性啁啾对自相似脉冲进行了啁啾补偿光纤设计。首先利用色散补偿光纤得到了半峰全宽为52.6fs、峰值功率为684.5W的超短脉冲输出。在此基础上研究了色散渐增的补偿光纤设计,讨论了色散线性渐增光纤和色散指数渐增光纤对自相似脉冲的压缩影响。当色散渐增系数取1km-1,5km-1,10km-1时,通过数值仿真得出了最短的输出脉宽、峰值功率以及所需的补偿光纤长度。结果表明,色散渐增光纤能缩短补偿光纤的长度,减小脉冲压缩时产生的损耗,得到半峰全宽为61.8fs和64.4fs的高功率超短脉冲输出。这一结果对自相似脉冲压缩光纤的设计是有帮助的。 相似文献
5.
利用块状介质进行飞秒强激光脉冲的腔外压缩 总被引:1,自引:0,他引:1
高强度飞秒激光脉冲的腔外压缩是获得高次谐波阿秒脉冲驱动源的必要手段.实验研究了超强超短飞秒激光脉冲在经过块状介质后的光谱展宽和色散补偿压缩现象.单脉冲能量0.26 mJ,脉宽50 fs的激光脉冲经透镜在空气中聚焦后再入射到块状材料上,出射脉冲光谱被展宽到接近40 nm.由于在块状材料中的自聚焦效应,出射光束质量变好并保持较小的空间啁啾.利用熔融石英棱镜对补偿带有正色散的出射脉冲,最后得到>0.1 mJ,19 fs的压缩脉冲.利用SPIDER装置测量了出射脉冲的脉宽和光谱相位.整个系统的能量效率大约为35%,压缩后的激光脉冲具有很好的空间分布和平滑的时域包络.实验结果实现了利用块状材料对飞秒激光脉冲的腔外压缩,这种方法将适用于对更高能量飞秒脉冲的压缩. 相似文献
6.
自陡峭效应对相位共轭系统脉冲传输的影响 总被引:2,自引:1,他引:2
光学相位共轭(OPC)技术能够同时且高效地补偿光纤传输过程中色散及非线性效应所导致的信号失真,且该技术同脉冲调制方式无关。从理论上分析了在自陡峭效应(SS)作用下高斯脉冲信号在中距相位共轭系统中的传输演化特性,数值模拟了在其作用下超短飞秒高斯脉冲的动态传输过程,讨论了自陡峭效应对中距相位共轭系统复原性能的影响。结果表明自陡峭效应将导致高斯脉冲信号发生峰值漂移和脉冲后沿变陡,相位共轭系统不能补偿由此导致的脉冲失真和畸变。引入合适的色散可以减小这种信号失真,并使得相位共轭系统能够同时补偿由于色散、自相位调制和自陡峭效应而引起的信号失真。 相似文献
7.
反射式光栅对是一种具有负色散性质的器件,可用于飞秒激光脉冲的压缩和展宽,具有无材料色散的优点。给出了一种基于多台阶反射光栅的脉冲压缩装置。该装置为倍密度光栅结构,由两个周期分别为40μm和20μm的四台阶反射式光栅组成。实验得到的衍射效率可以达到70%以上,输入脉冲经过两个光栅的衍射后会按原路返回,从而达到色散补偿的效果。利用此压缩装置,脉冲宽度为66.8 fs的输入脉冲压缩至接近傅里叶变换极限脉冲,即46.6 fs,由此证明只要多台阶光栅效率足够高,此装置就有可能成为不同于棱镜对进行飞秒脉冲腔内和腔外压缩的另一种途径。 相似文献
8.
9.
半导体激光器发出的光束具有较大的发散角且存在像散,严重影响了其应用。基于对半导体激光器远场分布的准确了解,提出了一种二元光学消像散准直器件的设计方法,并给出了详细的设计原理及过程。依据已知光束等相位面的具体分布(光束的像散因子也包含在其中),可得到二元光学器件的相位分布,使光束经过此二元光学器件后,等相位面成为平面,达到了准直、消像散的目的。此方法简单、直观,具有很高的准确性和可行性。所得二元光学器件表面具有多位相的浮雕结构。 相似文献
10.
11.
Bi-end dispersion compensation (DC) for ultralong nonreturn-to-zero (NRZ) optical transmission system is studied. Both the loss and dispersion of the transmission fiber are periodically compensated. Two dispersive elements are placed at the input and output ends of a compensation period, respectively, to compensate for fiber dispersion. The pulse compression owing to self-phase modulation (SPM) can be adjusted by the compensation ratios of the dispersive elements at the two ends of a compensation period. Therefore, the pulse compression can be optimized and the system performance can be improved to compare with the system with either pre- or postdispersion compensation. The rules to design the system are considered. The transmission system of 10-Gb/s bit rate, 9000-km transmission distance, and 100-km compensation period is taken as an example. The second-order fiber dispersion is assumed to be completely compensated. Wave equation is numerically solved to study the system performance which is represented by Q factor. The relations of several system parameters and Q factor are studied. The system parameters include the compensation ratios of the dispersive elements at the two ends of a compensation period, dispersion of transmission fiber, signal power, and the compensation ratios of third-order fiber dispersion. If the third-order fiber dispersion cannot be completely compensated, it is found that one can use a higher signal power to improve the system performance 相似文献
12.
Comb-like profiled fibre for efficient generation of high quality 160 GHz sub-picosecond soliton train 总被引:1,自引:0,他引:1
A comb-like profiled fibre (CPF), an alternate concatenation of a dispersive fibre and nonlinear fibre, is capable of emulating an arbitrary dispersion profile over distance for high quality optical pulse compression. It is demonstrated experimentally that CPF is efficient for the reshaping of an optical beat signal into a high quality 160 GHz 730 fs soliton pulse train with remarkably low noise, while stimulated Brillouin scattering was well suppressed. 相似文献
13.
Kunimatsu D. Xu C.Q. Pelusi M.D. Wang X. Kikuchi K. Ito H. Suzuki A. 《Photonics Technology Letters, IEEE》2000,12(12):1621-1623
We demonstrate for the first time the feasibility of 600-fs pulse transmission over 144 km using midway optical phase conjugation via a cascaded second-order process in a periodically poled LiNbO3 waveguide. The output pulses are negligibly distorted and broadened to 680 fs. This result could not be obtained without complete compensation for fourth-order dispersion performed by midway optical phase conjugation 相似文献
14.
We derive an expression for the temporal fractional Talbot effect in delay lines with arbitrary orders of dispersion. We then demonstrate, experimentally and by numerical simulations, that a simple device consisting of a number of uniform fiber Bragg gratings or of waveguides can serve for such a tailored dispersive delay line for periodic optical pulses. The device produces temporally delayed and phase-shifted replicas of the original pulses, similarly to what happens in dispersive delay lines in the fractional Talbot effect. Such devices can be useful for compensation for the nonquadratic spectral phase of diode lasers, of dispersive elements in systems used for temporal imaging, real-time spectral analysis, and periodic pulse generation. 相似文献
15.
基于频域分析的光学相干显微镜中的色散补偿 总被引:1,自引:0,他引:1
提出基于频域分析的色散补偿方法,对光学相干显微镜的干涉信号进行快速傅里叶变换,得到频率幅值极大值对应的平均波数,将提取的解包裹后的相位以平均波数为中心做多项式拟合,得到二阶色散系数。实验中,通过在参考臂中插入不同厚度的色散介质来引入两个干涉臂色散介质的光程差,并求得相应的二阶色散系数。通过最小二乘线性拟合,证实了二阶色散系数和色散介质的相对厚度具有很好的线性关系。根据该线性关系,可以在参考臂中插入适当厚度的色散介质来完全补偿干涉系统的二阶色散。 相似文献
16.
啁啾光脉冲在高阶色散控制光纤链中的稳定传输 总被引:6,自引:2,他引:4
基于一种二阶和三阶色散补偿的光纤级联系统模型 ,用数值法对啁啾皮秒光脉冲作了传输模拟。结果表明 ,完全补偿的高阶色散控制系统消除了三阶色散所引起的脉冲边沿部的振荡 ,减弱了脉冲峰的时间移动 ;另外 ,在确定的配置下 ,给输入脉冲附加一最佳的频率啁啾 ,可使得色散控制孤子稳定传输。脉冲宽度和啁啾以及光强度都围绕在初始值附近波动 ,在每个补偿周期末端 ,基本恢复到初始值 ;最佳啁啾的选取与二阶色散的配置有关 ,与三阶色散的配置无关 ;文中画出了 10 0Gbit/s码率的 64位随机高斯光脉冲序列在完全补偿系统中传输 10 0 0 0km后的眼图。由清晰的眼图可知 ,这种完全补偿系统减弱了脉冲之间的相互作用 相似文献
17.
18.
报道了一种新型的重复频率为10 GHz,脉宽为5.3 ps,抖动为184 fs的高稳定光短脉冲源.将大信号调制半导体激光器产生的10 GHz光脉冲,先送入LiNbO3电光相位调制器增强负啁啾,并使光谱进一步展宽,再通过色散补偿光纤(DCF)压缩脉冲啁啾,可得到光短脉冲.由于大信号调制激光器输出的光脉冲本身具有负啁啾,而通过相位调制器的光脉冲在不同的时间间隔内既有正啁啾也有负啁啾,通过适当调整进入相位调制器的光脉冲时延,使其通过相位调制器后累加产生更大的负啁啾,再利用正色散光纤压缩啁啾,从而得到低抖动且无基座的光短脉冲. 相似文献
19.
The dominant penalties are wavelength chirp, line broadening due to optical back reflection, and mode partition noise due to insufficient side-mode suppression. Experimental results on pulse compression at 1550 nm and on penalty reduction by dispersion compensation are presented. The dispersion compensation is achieved by adding a negative dispersive fiber link to a standard fiber link with positive dispersion at 1550 nm. In this way it was possible to transmit 5 Gb/s over a 111-km fiber link 相似文献
20.
《Lightwave Technology, Journal of》2008,26(15):2513-2520