排序方式: 共有18条查询结果,搜索用时 31 毫秒
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Knippels G.M.H. van der Meer A.F.G. Oepts D. van Amersfoort P.W. 《Quantum Electronics, IEEE Journal of》1997,33(1):10-17
We have investigated the optical output of the free-electron laser for infrared experiments (FELIX) when it is driven by an electron beam with a ramped energy. We show that the applied slow ramp on the electron beam energy leads to a frequency chirp on each picosecond optical pulse. Typical values for the chirp are 0.2% frequency sweep across a 1.5-ps-long optical pulse. The optical pulses were analyzed with a double-grating pair and with a second-order autocorrelator. The pulse duration was reduced in the double-grating pair by 20%. A linear dependence of the chirp on the cavity desynchronization was measured 相似文献
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V. I. Zhulin E. H. Haselhoff P. W. van Amersfoort 《Journal of Infrared, Millimeter and Terahertz Waves》1995,16(1):327-337
The Free-Electron Laser user facility FELIX produces picosecond optical pulses in the wavelength range of 5–110μm. The proposed installation of a new undulator with a larger magnetic period would allow extension towards considerably longer wavelengths. This would result in the production of extremely short, far-infrared pulses, with a duration of a single optical period or even less. In order to investigate the pulse propagation for free-electron lasers operating in the long wavelength limit, a three-dimensional simulation code was developed. Using the FELIX parameters, with the addition of a long-period undulator, the effects of slippage, diffraction losses, changes in the filling factor, as well as the effects of the optical cavity geometry were studied for wavelengths up to 300μm, with electron pulses in the ps regime. It is shown that slippage effects are less restrictive for long wavelength operation than the increasing losses due to optical beam diffraction. 相似文献
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Amersfoort M.R. de Boer C.R. Verbeek B.H. Demeester P. Looyen A. van der Tol J.J.G.M. 《Photonics Technology Letters, IEEE》1994,6(1):62-64
A 4-channel phased-array wavelength division demultiplexer with 1.8 nm channel spacing at 1.54 μm has been monolithically integrated with photodetectors in InP/InGaAsP. On chip losses are 3.5 to 4.5 dB. These are the lowest losses reported so far for demultiplexers monolithically integrated with photodetectors. Nearest neighbor crosstalk ranges from -12 to -21 dB 相似文献
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Bakker R.J. Jaroszynski D.A. van der Meer A.F.G. Oepts D. van Amersfoort P.W. 《Quantum Electronics, IEEE Journal of》1994,30(7):1635-1644
The Free-Electron Laser for Infrared eXperiments (FELIX) offers a unique combination of short electron bunches and long wavelengths, i.e. a slippage parameter μc ranging up to 10. As a consequence, pronounced short-pulse effects can be observed. In this paper the experimental observation of two of these effects is discussed, namely the occurrence of limit-cycle oscillations and the feasibility of tuning of the micropulse duration. The stable limit-cycle oscillation of the macropulse power is due to a modulation of the optical micropulse shape. This is a consequence of a combination of high optical power and short pulses. The former causes synchrotron oscillations of the electrons and the effect is, therefore, closely related to spiking phenomena. The short-pulse nature of FELIX ensures that the oscillations do not evolve into the chaotic behavior normally associated with spiking and the sideband instability. Experimental results are compared with numerical simulations 相似文献
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Weits H.H. Knippels G.M.H. van Werkhoven G.H.C. Oepts D. van Amersfoort P.W. 《Quantum Electronics, IEEE Journal of》1997,33(3):314-323
In the strong-slippage regime of a free-electron laser, the optical pulse inside the resonator is composed of a series of subsequently growing and decaying subpulses due to a limit-cycle oscillation. The picosecond time structure of the outcoupled pulses can be quite different from that of the intracavity pulse, in case of outcoupling through a hole and for specific resonator parameters. This is demonstrated by autocorrelation measurements and corroborated by simulations 相似文献
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Hole coupling in free electron lasers 总被引:1,自引:0,他引:1
Faatz B. Best R.W.B. Oepts D. van Amersfoort P.W. 《Quantum Electronics, IEEE Journal of》1993,29(7):2229-2238
Numerical simulations of the performance of a far-infrared free electron laser with an aperture in the upstream cavity mirror are presented. Two different applications of mirror apertures are studied: broadband extraction of radiation and injection of the electron beam. The emphasis is on the effect of the aperture on the amplitude of the higher-order transverse modes. It is shown that the mode distribution at saturation can be greatly influenced by variation of the mirror radius of curvature. A simple formula which is quite useful for predicting the dominant higher-order modes is derived. This permits optimization of the cavity with respect to the application in question 相似文献
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Amersfoort M.R. de Boer C.R. van Ham F.P.G.M. Smit M.K. Demeester T. van der Tol J.J.G.M. Kuntze A. 《Electronics letters》1994,30(4):300-302
A four-channel phased-array wavelength demultiplexer with a flattened wavelength response has been realised for the first time in InP/InGaAsP at 1.54 μm by employing multimode output waveguides. The device has 2 nm channel spacing and a flat response (within 1 dB) of 17 nm 相似文献