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101.
双腔双波长交叉锁模钛宝石飞秒激光器的研究 总被引:3,自引:0,他引:3
本文建立了一台双光束泵浦的双腔双波长交叉锁模Ti:Sapphire激光器,实现了中心波长为755nm和845nm的双波长同步锁模输出,得到了脉宽分别为28fs和34fs的锁模脉冲. 相似文献
102.
Using Hefei Synchrotron radiation as X-ray source and photoresist PMMA as recording medium, soft X-ray contact microscopic imaging experiment on hydrated leaf epidermal cells of a kind of dicotyledon is performed and its latent image is read out by a light microscope. Several main factors degrading the resolution of the image are discussed in detail. 相似文献
103.
Yonggang Zhang Yi Gu Cheng Zhu Guoqiang Hao Aizhen Li Tiandong Liu 《Infrared Physics & Technology》2006,47(3):257-262
Using homo-junction structure and relative thin linear graded InxGa1−xAs as the buffer layer, extended wavelength InGaAs PIN photodetectors with cut-off wavelength of 2.2 and 2.5 μm at room temperature have been grown by using GSMBE, and their performance over a wide temperature range have been extensively investigated. For those 2.2 or 2.5 μm detectors with 100 μm diameter, the typical dark current (VR = 10 mV) and R0A are 57 nA/10.3 Ω cm2 or 67 nA/12.7 Ω cm2 at 290 K, and 84 pA/4.70 kΩ cm2 or 161 pA/3.12 kΩ cm2 at 210 K respectively. The thermal activation energies of the dark current are 0.447 eV or 0.404 eV for 2.2 or 2.5 μm detectors respectively. 相似文献
104.
用半导体激光器作调制器的双波长可调谐锁模光纤激光器 总被引:5,自引:2,他引:3
提出一种用法布里—珀罗腔半导体激光器(F—PLD)作调制器,用线性凋啾光栅(LCFG)进行波长选择的双波长环形腔主动锁模光纤激光器。利用线性凋啾光栅在腔内的色散效应使两个波长的光脉冲通过饵光纤(EDF)时在时域上分开,从而威小了不同波长的光脉冲同时通过饵光纤时造成的竞争,因此可以在室温下获得波长间隔较小的稳定的双波长光脉冲输出。实验中成功地获得了重复频率约为2GHz,波长间隔为0.92nm的稳定双波长光脉冲,并通过调谐线性凋啾光栅中心波长的位置使激光波长可以在约3nm范围内调谐。 相似文献
105.
Optical multistability of a Fabry-Perot semiconductor laser is analyzed when multi-optical inputs detuned from the cavity-resonant wavelength of a semiconductor laser are injected. Many split branches are shown to be produced in the optical output versus optical input characteristics for different detuned optical inputs. It is also shown that optical outputs can be switched in any one of the optical input wavelengths by optical input pulses, based on the optical output versus input characteristics with multi-split branches. 相似文献
106.
The behaviour of an array of photonic crystal waveguides is numerically investigated. It is shown that high dispersion may
be achieved in the telecommunication window around 1550 nm, with a device whose dimensions are in the order of half a mm2. 相似文献
107.
In this paper, the chromatic dispersion and chromatic dispersion slope of two kinds of triple-clad single-mode fibers with a depressed index inner cladding named WI- and WII-type were examined. A feasible approach to calculate chromatic dispersion and higher-order dispersion was established successfully, and the influences made by the optical parameters and geometric parameters on the chromatic dispersion coefficient and its slope were analyzed in detail. The calculated results show that the optical parameter R2, which symbolizes the third cladding effect, has a strong impact on the chromatic dispersion coefficient and the chromatic dispersion slope, and the degrees of such impact are closely related to the other parameters. 相似文献
108.
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110.
In this paper, we propose the implementation of waveguide-coupled ring resonators in photonic crystal integrated circuits. Using two-dimensional finite difference time domain (2D FDTD) method, we study the spectral characteristics of a waveguide-coupled ring carved in two-dimensional photonic crystal of square lattice (2D SLPC) and based on the results, we suitably modify the structure geometry to establish its performance as a ring resonator. We further investigate the effects of ring dimension and crystal parameters on the resonance properties of the ring resonator. 相似文献