排序方式: 共有36条查询结果,搜索用时 31 毫秒
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高能激光广泛应用于材料加工、科学研究、空间碎片清除、军事应用等领域。二极管泵浦高能激光具有结构紧凑,系统简单、全电驱无限弹仓的特点,近年来,各类二极管泵浦高能激光围绕着同时实现高功率、高效率、高光束质量这一总目标发展迅速。详细综述了国内外高平均功率块状固体激光、高功率可见光波段激光、高峰值功率激光、高功率光纤激光、碱金属蒸气激光等二极管泵浦高能激光的研究进展,并对其发展趋势进行了展望。 相似文献
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微波消解-可见分光光度法测定土壤中的总铬 总被引:1,自引:0,他引:1
通过对3种常用微波消解实例进行试验,得出了微波消解土壤样品最佳的样品处理条件和仪器控制条件,优化了土壤中总铬的检测方法。以HNO3-H2O2-HF消解体系消解土壤样品效果最佳,该方法测定总铬的检出限为5m g/kg,两个土壤样品5次平行测定的RSD分别为0.49%和1.98%,加标回收率分别为97.30%和98.20%。微波消解-可见分光光度法测定土壤中的总铬是一种快速、准确、节约酸用量且低环境污染的检测方法。 相似文献
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随着光纤陀螺研究的不断进展,对陀螺光源的稳定性的要求也越来越高。SFS(超荧光光纤光源)正是应用于高精度陀螺要求的宽带光源,它的平均波长和功率的温度稳定性直接影响着光纤陀螺的性能。从SFS的特性分析对其驱动系统进行了设计,提出并实现了温度稳定性的控制方案。 相似文献
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This paper reports that, based on the electromagnetic
scattering theory of the multipole method, a high-quality hollow beam is
produced through a selectively liquid-filled photonic crystal fibre.
Instead of a doughnut shape, a typical hollow beam is produced by
other methods; the mode-field images of the hollow-beam photonic
crystal fibre satisfy sixth-order rotation symmetry, according to
the symmetry of the photonic crystal fibre (PCF) structure. A dark
spot size of the liquid-filled photonic crystal fibre-generated
hollow beam can be tuned by inserting liquid into the cladding region
and varying the photonic crystal fibre structure parameters. The
liquid-filled PCF makes a convenient and flexible tool for the
guiding and trapping of atoms and the creation of all-fibre optical
tweezers. 相似文献
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This paper proposes three kinds of tapered holey fibres with a multi-layer of holes whose pitch of air holes at the end of untapered and tapered are 5.8 μm and 1.8 μm. The central wavelength which locates in the anomalous dispersion region is 1.55 μm. An adaptive split-step Fourier method is numerically used to study the pulse propagation in tapered holey fibres. For the considered convex tapered holey fibre, at a wavelength of 1.55 μm, a compression factor of 136.7 can be achieved by initial width of 800 fs propagation through a length of 0.8 m. It demonstrates that in anomalous dispersion region, pulse can be compressed with the increase of nonlinearity coefficient and the decrease of dispersion coefficient. 相似文献
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A kind of high birefringence SF6 soft glass photonic crystal fiber (HBSF6-PCF) is proposed. The properties of birefringence, dispersion, nonlinear coefficient and the transmission characteristics are studied by the multipole method and the adaptive split-step Fourier method. The numerical results show that the birefringence and the nonlinear coefficient reach the orders of 10^-2 and 10^-1, respectively. In addition, the HBSF6-PCFs can generate very smooth supercontinuum spectra when illuminated with femtosecond pulsed light of 1064 nm. It is found that up to 800nm spectral width (evaluated at -5dB from the peak) is achieved. Therefore, the advantage of the HBSF6-PCFs is such that a high birefringence, a high nonlinearity and a smooth supercontinuum are perfectly combined in them. 相似文献
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设计了一种高双折射高非线性纳米结构光子晶体光纤,利用电磁场散射的多极理论研究了这种光纤的双折射、基模模场、色散以及非线性特性.数值研究发现,加大纤芯及包层空气孔的非对称程度,可使双折射变大,其双折射最大值可达1.918×10-2.通过调节孔节距大小,可将双折射最大值调至所需波长处,孔节距为400nm的纳米光子晶体光纤在800nm波长处非线性系数高达0.2m-1.W-1,同时在750—1000nm的波段有较大的双折射值,高双折射和高非线性在纳米结构光子晶体光纤中实现了完美的结合.对新型纳米光子器件的研制和集成光学的发展具有重要意义. 相似文献