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61.
A simple configuration is proposed to perform wavelength switching in actively mode-locked fiber ring lasers, in which a sampled fiber Bragg grating and a tunable optical filter are cascaded in the ring cavity to exactly select the operating wavelength. The switching of four wavelengths with a spacing of 1.6 nm is obtained. The experimental results demonstrate that this technique is reliable and convenient. 相似文献
62.
Theory of passively mode-locked lasers with self-frequency shift and saturable absorber response
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A general theoretical model for passively mode-locked lasers is presented, in which both the self-frequency shift and either a fast or a slow saturable absorber response are taken into account. An exact soliton-like solution and condition for its existence are obtained under a definite compatible condition. The stability of the solution is analyzed by using a variational method, and a parameter region, in which the solution is linearly stable, is acquired theoretically. To verify the theoretical predictions, a typical example is given for stable pulse propagation over a long distance. The numerical results show that the soliton-like solution is stable under some perturbations within the linearly stable region and an arbitrary Gaussian pulse converges to the exact soliton-like solution after evolution in a distance. 相似文献
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论述了在对撞锁模染料激光器中必然存在锁模脉冲列耦合效应,此效应使输出脉冲较宽,且脉宽不稳定。用适当加厚锁模染料层等办法减弱该效应会使脉冲变窄且脉宽稳定。 相似文献
66.
Pezzato M Lunga GD Baratto MC Sinicropi A Pogni R Basosi R 《Magnetic resonance in chemistry : MRC》2007,45(10):846-849
In this paper the Cu(II)-bis-(glycinato) complex has been analysed in solution by applying a combined approach of multifrequency EPR and DFT/PCM calculations. The accuracy in the determination of magnetic parameters has been reached by the use of a unique simulation program (COSMOS) for the whole range of temperatures analysed and by the error analysis. A change in magnetic parameters was envisaged in the 243-253 K range of temperature, and was interpreted in terms of stabilization, near the freezing point of the solution, of one of the isomers of the complex. A DFT/PCM computational model was crucial in assigning, on the basis of the experimental superhyperfine interaction value, the isomer to the trans form. 相似文献
67.
I. P. Akimchenko K. V. Kisseleva V. V. Krasnopevtsev A. G. Touryanski V. S. Vavilov 《辐射效应与固体损伤》2013,168(1-4):7-11
Two-photon excitation spectrum of the luminescence emitted in the A T -band has been observed in KBr:In+ and NaBr:Tl+. The nonlinear excitation follows the A-band lineshape but reveals a feature, not present in one-photon spectrum, that may be interpreted as due to the forbidden 1 AIg →3AIu transition. The cross section of the process indicates that the two-photon transitions are indirect ones, allowed by phonons. The dependence of the emitted light intensity upon the direction of polarization of the exciting photons, makes it possible to identify the symmetry of the transitions. 相似文献
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利用连续波段内激光对两批光伏型碲镉汞探测器进行了激光辐照实验, 发现了两种不同的过饱和现象. 实验表明, 光伏型碲镉汞探测器在强光辐照下都会出现开路电压随光强增强而减小的过饱和现象, 明晰了PV型探测器在强光辐照下的一般规律性现象和由探测器个体差异导致的特殊现象. 从等效电路模型出发, 剖析了两种过饱和现象的发生条件, 建立了数值计算的理论模型, 对两种过饱和现象进行了数值模拟, 计算结果与实验结果符合得较好. 研究表明, 光伏型碲镉汞探测器在波段内强光辐照下引起的过饱和现象有两种产生机理, 一种是热效应引起的暗电流增大机理; 另一种是探测器材料中缺陷引起的漏电流增大机理.
关键词:
波段内连续激光
光伏型碲镉汞探测器
过饱和现象 相似文献
70.
《Quaestiones Mathematicae》2013,36(1):119-134
The naive concept of a DW complex is that of a differential space that can be built up from cells and whose differential structure is defined in terms of differential structures on Euclidean unit closed balls. This concept stems from an analogue in the category of topological spaces: the so-called CW complex. The paper goes as far as investigating the underlying topological space of a DW complex. 相似文献