排序方式: 共有85条查询结果,搜索用时 125 毫秒
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We consider multisoliton patterns in the model of a synchronously pumped fiber-loop resonator. An essential difference of this system from its long-line counterpart is that, due to the finite length, dynamical regimes may be observed that would be unstable in the infinitely long line. For the case when the effective instability gain, produced by competition of the modulational instability (MI) of the flat background and losses, is small, we have consistently derived a special form of the complex Ginzburg-Landau equation for a perturbation above the continuous wave (cw) background. It predicts bound states of pulses with a uniquely determined ratio of the pulse width to the separation between them. Direct numerical simulations have produced regular soliton lattices at small values of the feeding pulse power, and irregular patterns at larger powers. Evidence for a phase transition between the lattice and gas phases in the model is found numerically. At low power, the width-to-sep aration ratio as found numerically proves to be quite close to the analytically predicted value. We also compare our results with recently published experimental observations of MI-stimulated formation of a pulse array in a mode-locked fiber laser. 相似文献
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Chalcogenide glass photonic crystals 总被引:1,自引:0,他引:1
Darren Freeman Christian Grillet Michael W. Lee Cameron L.C. Smith Yinlan Ruan Andrei Rode Maryla Krolikowska Snjezana Tomljenovic-Hanic C.Martijn de Sterke Michael J. Steel Barry Luther-Davies Steve Madden David J. Moss Yong-Hee Lee Benjamin J. Eggleton 《Photonics and Nanostructures》2008,6(1):3-VII
All-optical switching devices are based on a material possessing a nonlinear optical response, enabling light to control light, and are enjoying renewed interest. Photonic crystals are a promising platform for realizing compact all-optical switches operating at very low power and integrated on an optical integrated circuit. In this review, we show that by making photonic crystals from a highly nonlinear chalcogenide glass, we have the potential to integrate a variety of active devices into a photonic chip. We describe the fabrication and testing of two-dimensional Ge33As12 Se55 chalcogenide glass photonic crystal membrane devices (waveguides and microcavities). We then demonstrate the ability to post-tune the devices using the material photosensitivity. In one proposal we hope to introduce a double-heterostructure microcavity using the photosensitivity alone. 相似文献
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Temperature dependence of pressure broadening of the N = 1− fine structure oxygen line at 118.75 GHz
M.Yu. Tretyakov M.A. Koshelev I.A. Koval V.V. Parshin L.M. Kukin L.I. Fedoseev Yu.A. Dryagin A.F. Andriyanov 《Journal of Molecular Spectroscopy》2007,241(1):109-111
The absorption profile of the N = 1− fine structure line of oxygen was recorded by a resonator spectrometer at a frequency range of 110-130 GHz at atmospheric pressure and different temperatures ranging from −21 °C up to +22 °C. Analysis of the observed line shape allowed determination of the temperature dependence of the line pressure broadening. The measured value of the temperature exponent is n = 0.74(5) for self-broadening. Consistency of the measurements is supported by simultaneous measurements of the line intensity, the line mixing parameter and the line center frequency, and by comparison of obtained values with previously known data. 相似文献
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We theoretically investigate the characteristics of an unsymmetric resonator with single Nd:YAG rod to find the best condition for getting the highly efficient intracavity second harmonics. The beam quality is analyzed with ABCD matrixes including the thermal characteristic of Nd:YAG rod. The analysis is focused on stability, , beam waist and mode-volume of laser beam inside resonator. The results show that the smallest beam waist and a large TEM00 mode-volume can be achieved when a Nd:YAG rod closely contacts one of the laser mirrors. This means that the second harmonics of intracavity type generated under these conditions can be highly efficient. 相似文献
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Dr.‐Ing. Ingolf Bork 《Physik in unserer Zeit》2015,46(3):144-147
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Ali Khanchehgardan Ghader RezazadehRasool Shabani 《International Journal of Solids and Structures》2014
Present investigation is focused on studying the effect of mass diffusion on the quality factor of the micro-beam resonators. Equation of motion is obtained using Hamilton’s principle and also the equations of thermo-diffusive elastic damping are established using two dimensional non-Fourier heat conduction and non-Fickian mass diffusion models. Free vibration of a clamped–clamped micro-beam with isothermal boundary conditions at both ends, and also a cantilever micro-beam with adiabatic boundary condition assumption at the free end, is studied using Galerkin reduced order model formulation for the first mode of vibration. Mass diffusion effects on the damping ratio are studied for the various micro-beam thicknesses and temperatures and the obtained results are compared with the results of a model in which the mass diffusion effect is ignored. In addition to the classic critical thickness of thermoelastic damping, a new critical thickness concerning mass diffusion is introduced. 相似文献