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101.
Uwe Bandelow Mindaugas Radziunas Andrei Vladimirov Bernd Hüttl Ronald Kaiser 《Optical and Quantum Electronics》2006,38(4-6):495-512
We study both theoretically and experimentally typical operation regimes of 40 GHz monolithic mode-locked lasers. The underlying
Traveling Wave Equation model reveals quantitative agreement for characteristics of the fundamental mode-locking as pulse
width and repetition frequency tuning, as well as qualitative agreement with the experiments for other dynamic regimes. Especially
the appearance of stable harmonic mode-locking at 80 GHz has been predicted theoretically and confirmed by measurements. Furthermore,
we derive and apply a simplified Delay-Differential-Equation model which guides us to a qualitative analysis of bifurcations
responsible for the appearance and the breakup of different mode-locking regimes. Higher harmonics of mode-locking are predicted
by this model as well. 相似文献
102.
Juray De Wilde Denis Constales Geraldine J. Heynderickx Guy B. Marin 《International Journal of Multiphase Flow》2007
The propagation speeds of linear waves in gas–solid suspensions depend strongly on the solids volume fraction and the wave frequency. The latter is due to gas–solid momentum transfer and allows a simple test on filtered gas–solid momentum transfer models. Such models may predict linear wave propagation speeds different from those obtained with the non-filtered model at wave frequencies higher than the filter frequency, but not at wave frequencies lower than the filter frequency. 相似文献
103.
Frank Natterer Olga Klyubina 《计算数学(英文版)》2007,25(3):368-373
We study the initial value problem of the Helmholtz equation with spatially variable wave number. We show that it can be stabilized by suppressing the evanescent waves. The stabilized Helmholtz equation can be solved numerically by a marching scheme combined with FFT. The resulting algorithm has complexity n^2 log n on a n x n grid. We demonstrate the efficacy of the method by numerical examples with caustics. For the Maxwell equation the same treatment is possible after reducing it to a second order system. We show how the method can be used for inverse problems arising in acoustic tomography and microwave imaging. 相似文献
104.
A Series of Exact Solutions of (2+1)-Dimensional CDGKS Equation 总被引:1,自引:0,他引:1
YANG Zong-Hang 《理论物理通讯》2006,46(11)
An algebraic method with symbolic computation is devised to uniformly construct a series of exact solutions of the (2 1)-dimensional Caudrey-Dodd-Gibbon-Kotera-Sawda equation. The solutions obtained in this paper include solitary wave solutions, rational solutions, triangular periodic solutions, Jacobi and Weierstrass doubly periodic solutions. Among them, the Jacobi periodic solutions exactly degenerate to the solutions at a certain limit condition. Compared with most existing tanh method, the method used here can give new and more general solutions. More importantly, this method provides a guideline to classify the various types of the solution according to some parameters. 相似文献
105.
The energy exchange between the pumping laser and FIR signal in the optically pumped FIR laser (OPFIRL) system was studied. The iteration method has been used to calculate the power density of the pumping and FIR signals at any point along the optical axis of the sample tube. It was found that the power density of the FIR signal did not always increase along the length of the laser tube. There was a maximum FIR power density at the appropriate point in the sample tube. If the distance of maximum power point from the entrance of the OPFIRL tube was taken as the length of sample tube Zopt, the maximum FIR laser output should be obtained. This was the optimum length of OPFIRL tube. The value of Zopt was closely related to the parameter of OPFIRL such as the pumping power density, the pumping detuning and the frequency of the FIR laser. The energy-exchange and the maximum output of the fir laser were calculated under the ideal condition. 相似文献
106.
热效应对光折变晶体两波耦合的特性影响的理论分析 总被引:3,自引:1,他引:2
用一种模型对两波耦合进行了分析,导出了强度相位的解析式,对影响两波耦合的参数进行了理论分析。分析了对BaTiO3光折变晶体的两波耦合的测量结果。 相似文献
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