共查询到20条相似文献,搜索用时 15 毫秒
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P. T. Lang W. J. Knott I. Leipold K. F. Renk A. D. Semenov G. N. Gol'tsman 《Journal of Infrared, Millimeter and Terahertz Waves》1992,13(3):373-380
We report on generation and detection of intense pulsed radiation with frequency tunability in the infrared and far-infrared spectral regions. Infrared radiation is generated with a transversally electrically excited high pressure CO2 laser. A laser pulse of a total duration of about 300 ns consisted, due to self mode locking, of a series of single pulses, some with pulse durations of less than 450 ps and peak powers larger than 20 MW. Using these pulses for optical with durations less than 400 ps were obtained. For detection a new ultrafast superconducting detector was used. 相似文献
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Basov N. Kriukov P. Letokhov V. Senatskii Yu. 《Quantum Electronics, IEEE Journal of》1968,4(10):606-609
During the last two years since the 1966 Iternational Quantum Electronics Conference further progress toward obtaining high-power light pulses has taken place. An effective method of ultrashort light pulse generation (mode locking) has been developed, further development of the method of coherent amplification of light pulses has been recorded, and new prospective ideas have been put forward. The present paper briefly reports on the data obtained by us in these directions. 相似文献
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V. Loyo-Maldonado H.K. Lee C.R. Stanley S.V. Rao K. Moutzouris M. Ebrahimzadeh J.S. Aitchison 《Photonics Technology Letters, IEEE》2003,15(3):428-430
We report a novel device capable of generating ultrashort electrical pulses on a coplanar waveguide (CPW) by means of optical rectification. The device consists of a completely passive GaAs-based optical waveguide, which is velocity matched to a CPW line. Optical pulses are injected into the device and electrical pulses are collected at the output. Experimental results obtained in the laboratory show the potential of this device for high speed optical-to-electrical conversion. 相似文献
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Kapetanakos C.A. Hafizi B. Milehberg H.M. Sprangle P. Hubbard R.F. Ting A. 《Quantum Electronics, IEEE Journal of》1999,35(4):565-576
This paper summarizes the results of analytical and numerical studies on a novel technique that is capable of providing high average power ultra broadband radiation that extends from approximately 2 to 16 μm. Such a spectrum has several potential applications, including telecommunications and remote sensing. Additional attractive features of the new source are its anticipated compact size, light weight, ruggedness, and affordable cost. The technique is based on the interaction of a beat wave with a nonlinear medium. The beat wave is formed from the mixing of two CO2 laser beams with closely spaced wavelengths, such as 9.5 and 9.6 μm. The discrete ultrabroad-band spectrum is generated in a nonlinear optical medium by the self-phase modulation process, a third-order nonlinearity. The long-wavelength portion of the spectrum, i.e., from 5 to 16 μm is produced directly from the interaction of the beat wave with a GaAs crystal. The short-wavelength portion of the spectrum is produced from the interaction of a frequency-doubled beat wave with a GaAs crystal following the chirping of the pulse by a different GaAs crystal and its subsequent optimal compression by a thin sapphire slab 相似文献
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A neodymium glass laser system capable of generating high-energy, ultrashort pulses at a convenient repetition rate is described. The effect of nonlinear frequency pulling on active mode locking is discussed. By minimizing the nonlinear frequency pulling, it is possible to routinely generate stable ~10-ps pulses at a 100-MHz repetition rate from the actively mode-locked oscillator. The regenerator amplifier increases the oscillator pulse energy to over 30 μJ at a 370-Hz repetition rate. Using intracavity self-phase modulation, the regenerative amplifier also broadens the pulse bandwidth to ~35 Å. By subsequent pulse compression while maintaining high energy, it is possible to produce 0.55-ps pulses with >10 μJ. An optical fiber pulse compressor further shortens the pulses to 30 fs (30 nJ), the shortest pulses ever generated at 1.054 μm from a neodymium laser system 相似文献
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J. Galán M. Sánchez-Raya R. López-Ahumada T. Sánchez-Rodríguez I. Martel R. Jiménez 《Microelectronics Journal》2014
This paper presents a design of low power and low noise, high speed readout front-end system for semiconductor detectors. The architecture comprises a folded cascode charge sensitive amplifier with gain enhancement, a pole-zero cancellation circuit and a complex shaper circuit with Gm-C topology. A local feedback amplifier based on a wide swing gain boosting scheme with dc level shifting has been used. The system has been fabricated in a 0.13-µm CMOS technology with a single 1.2-V supply voltage. Experimental results show the flexibility of the system where the key parameters, such as decay time, charge gain and peaking time can be tuned. For a nominal peaking time of 150 ns the power consumption of the entire channel is less than 5 mW. A power consumption-low noise tradeoff will be considered to match a detector capacitance of 5 pF. The output pulse has a peak amplitude of 200 mV for a charge of 10 fC from the detector and achieves a linearity better than 1% up to an input charge range of 12 fC. 相似文献
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A. M. Efremov V. I. Koshelev B. M. Koval’chuk V. V. Plisko K. N. Sukhushin 《Journal of Communications Technology and Electronics》2007,52(7):756-764
The results of investigation of the generation and radiation of high-power ultrawideband electromagnetic pulses are presented. The possibility of obtaining wave beams of radiation with orthogonal polarizations of the electric field is shown. The radiating system is a 16-element antenna array that can be separated into two subarrays operating in orthogonal polarizations and excited by pulses separated in time. Two design versions of orthogonal subarrays are studied. 相似文献
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V. A. Terekhov A. N. Man’ko E. N. Bormontov V. N. Levchenko S. Yu. Trebunskikh E. A. Tutov É. P. Domashevskaya 《Semiconductors》2004,38(12):1390-1393
The effect of pulsed electromagnetic radiation with a leading-edge duration of 1.4×10?9 s and a total pulse duration of ~11.5×10?9 s, a repetition rate of 10 kHz, and various pulse energies (?2.4×10?4 J) on Al/SiO2/Si structures is studied. Capacitance-voltage characteristics of such structures were measured before, during, and after exposure to ultrashort pulses. Changes dependent on the pulse energy caused by insulator polarization and a transformation of the nonequilibrium defect structure of the interface with the semiconductor as a result of the irradiation were found, as well as irreversible changes associated with a breakdown observed after the radiation was switched off. 相似文献
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强激光超短脉冲在非线性介质中传输引起的超加宽 总被引:2,自引:1,他引:1
利用以三阶非线性系数为基础的平面波理论,通过直接解非线性波动方程,研究强场(~10~(14)W/cm~2)作用下,超短脉冲(80fs)在非线性介质中传播所引起的光谱超加宽现象。在忽略色散效应的情况下,得到输出脉冲Stokes和反Stokes展宽的不对称性,并定量地解释了R.L.Fork等人的实验。 相似文献
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Nicholson J.W. Fini J.M. Bouteiller J.-C. Bromage J. Brar K. 《Lightwave Technology, Journal of》2004,22(1):71-78
We demonstrate a novel, high repetition rate, swept-wavelength Raman pump source. The pump is based on stretched femtosecond pulses, initially generated in a passively modelocked, erbium-doped, fiber laser, and wavelength shifted in highly nonlinear, dispersion shifted fiber. The pump wavelength has a linear sweep in time, with a repetition rate of 69 MHz. The pump has a center wavelength of 1470 nm, a full-width at half-maximum (FWHM) of 31 nm, and an average power of 350 mW. We characterize the pump by performing pump propagation experiments and electrical spectrum measurements of signal lasers amplified with the swept-wavelength pump. 相似文献
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Active and passive mode locking has been observed in an erbium doped fibre single ring laser. Pulse durations as short as 100 fs at a repetition rate of 300 GHz have been measured from an erbium doped fibre amplification stage placed at the output of the fibre ring. The ultrafast regime depends critically on the dynamical evolution of the light polarisation along the cavity.<> 相似文献
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Yu. A. Andreev V. I. Koshelev I. V. Romanchenko V. V. Rostov K. N. Sukhushin 《Journal of Communications Technology and Electronics》2013,58(4):297-306
A pulsed source of the ultrawideband radiation based on a nonlinear line and a single combined antenna is proposed. The frequency that corresponds to the maximum radiation spectrum can be tuned in the interval 0.5–1.3 GHz. The effective radiation potential of the source is 95–310 kV. 相似文献