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本文研究了光学频率梳输出的整形后飞秒脉冲激光和单频激光的干涉光谱。实验中光学频率梳和单频激光干涉的信号包括直流项、光学频率梳输出的脉冲激光相邻模式之间的干涉项和光学频率梳脉冲激光与单频激光之间的干涉项。实验上研究了光学频率梳脉冲激光与单频激光干涉信号间距和单频激光频率的关系,提供了一种快速直接测量单频激光频率的有效方法。研究了光学频率梳输出的飞秒脉冲光经过铷泡后与单频激光干涉信号和单频激光频率的关系,获得铷原子吸收光谱。该研究工作对于原子分子高精密光谱测量具有一定的意义。 相似文献
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光学元件是各类激光系统不可或缺的光学功能实现部件,其性能决定了激光系统的输出能力和光束质量。光学元件的激光损伤问题从激光发明起就一直伴随着激光技术的发展,随着激光新技术的发展和激光新应用的牵引,激光的波段、脉冲宽度以及重复频率等参数不断拓宽,使得激光损伤问题更加复杂,但万变不离其宗,激光损伤问题的核心是光学元件或光学材料对激光的吸收机制问题。从激光与光学材料相互作用的基本原理出发,以惯性约束聚变(ICF)激光驱动器应用的典型光学材料和光学元件为研究对象,回顾了针对光学元件的激光损伤问题开展的科研工作,总结了在此期间形成的关键技术和里程碑进展,同时也对依然困扰该领域的几类光学元件存在的问题瓶颈以及进一步研究发展趋势进行了展望。 相似文献
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激光等离子体加速器能够在cm尺度内产生GeV量级的高品质电子束,为研制台式化自由电子激光提供驱动源。但是受限于激光等离子体加速中的难点和现有技术发展,电子束的品质难以达到自由电子激光的需求,尤其在稳定性、发散角和能散等方面,阻碍了台式化自由电子激光的研制。介绍了基于激光等离子体加速器的自由电子激光的最新进展,整理了目前高增益自由电子激光实验过程中存在的主要挑战和对应的解决方案与实验进展,并展望未来的发展方向。最近的研究结果证明,通过控制和优化激光等离子体加速器的注入和加速过程产生的高品质电子束可以在指数增益区域实现自发辐射放大,产生高增益的辐射,这也推动基于激光等离子体加速器的自由电子激光研究进入了一个新的阶段。 相似文献
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A novel method of cavity ringdown spectroscopy is proposed to achieve high spectral resolution with tunable narrow bandwidth pulsed lasers. We demonstrate a cavity-tuned ringdown configuration in which only a single cavity mode is kept excited near the carrier frequency of a narrow bandwidth pulse laser. This is done simply by making a cavity resonance actively track the frequency reference served by the cw injection seed of the pulsed laser source. We present the servo mechanism used in the cavity resonance tracking, reliable procedures for transverse mode matching, and the evidence of single longitudinal mode excitation. The spectrometer performance is tested to record weak molecular overtone features of acetylene around the wavelength of 570 nm, showing cavity tracking stability within 5-MHz uncertainty which overcomes the bandwidth limit of pulsed laser sources itself. PACS 42.62.Fi; 42.60.Da; 33.20.Kf 相似文献
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A tunable, very narrow bandwidth, flashpumped dye laser is described. Publse energies up to 50 mJ at a bandwidth of less than
30 MHz, and with a divergence of 0.4 mrad, are obtained. Spectral narrowing and tuning is achieved by injection locking of
the pulsed laser to the radiation, of a tunable cw dye laser. The cavity is designed for single longitudinal and transverse
mode operation, with a mode diameter large enough to fill the active medium.
This work was supported in part by the Israel commission for Basic Research, and in part by a grant from the United States
Israel Binational Science Foundation (BSF), Jerusalem, Israel. 相似文献
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We demonstrate single higher-order transverse mode operation of a radially polarized Nd:YAG laser by using a polarization-selective and reflectivity-modulated output coupler. A narrow annular region with low reflectivity fabricated in a photonic crystal mirror behaves so as to select a higher-order transverse mode of a cylindrically symmetric laser beam. A double-ring-shaped radially polarized TM(02) mode beam is stably generated. 相似文献
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Achieving single-lobed far-field patterns of broad area laser diode with external cavity feedback 总被引:4,自引:0,他引:4
We demonstrate a technique for single transverse mode operation of high-power broad area laser diode (BAL). In the experiment, the HR mirror is used as an external cavity mirror and the grating is used as a wavelength selective component. By tiling the HR mirror and the grating, the number of transverse modes oscillating in the cavity can be limited and the spectral bandwidth of the laser diode can be reduced. A single-lobed near diffraction-limited laser beam with the beam divergence (FWHM) of 0.43°, the spectral line-width of 0.7 nm and the output power of 350 mW are obtained. With the feedback, the power density of the output laser beam is increased 6 times in comparison with the free running. 相似文献
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为了产生多种激光横模,以前的系统相对比较复杂,而且一般只能产生基横模和低阶横模,很难产生高阶横模,同时也很难观察到模竞争中一个频率抑制另一个频率的变化过程。基于猫眼谐振腔激光器和频率分裂技术,提出了一种新型的激光原理综合实验系统。该系统利用猫眼逆向器作为He-Ne激光器的一个腔镜,通过调节猫眼逆向器中两镜片间距可输出包括基横模、低阶横模、高阶横模在内的十余种典型横模,并可完成纵模、偏振、出光带宽等多种激光基本特性的实验。同时在基横模状态下,利用谐振腔内加入的石英晶体片可实现激光频率分裂及其频差调节。在此基础上又可实现完整的模竞争过程的观察。 相似文献
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为解决准横电磁(TEM)模波导工作带宽较窄的问题,提出采用金属贴片电磁带隙(EBG)结构在金属波导中创建准TEM波.通过理论分析和数值计算,研究金属贴片EBG结构创建准TEM波导对展宽带宽、改善传输特性和增强准TEM波电场分布均匀性的作用.模拟结果表明,在频率14 GHz附近,金属贴片EBG将TE10模成功转换成准TEM模,转换带宽达到1.7 GHz,且在波导横截面83.9%的面积上电场分布均匀性达到84.7%.
关键词:
电磁带隙
金属贴片电磁带隙结构
磁导体
准横电磁模波导 相似文献
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Design and technology demonstration of compact, narrow bandwidth, high repetition rate, tunable SLM dye lasers in two different
configurations, namely Littrow and grazing incidence grating (GIG), were carried out in our lab at BARC, India. The single
longitudinal mode (SLM) dye laser generates single-mode laser beams of ∼400 MHz (GIG configuration) and ∼600 MHz (Littrow
configuration) bandwidth. Detailed performance studies of the Littrow and GIG dye laser resonators showed that GIG dye laser
results in narrower linewidth and broad mode hop free wavelength scanning over 70 GHz. In this paper we present experimental
studies carried out on the high repetition rate SLM dye laser system. 相似文献
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A new type of laser reflector is described in which the laser beam is split by frustrated total internal reflection and the components combined again. It has the properties of high reflectivity, high damage resistance, wide bandwidth and variable reflectivity. The design of two particular reflectors is discussed and their performance evaluated. One of these reflectors has the property of lateral inversion of the reflected beam, which is found to aid transverse mode selection in a ruby laser. As an application of the reflectors, a damage free, single transverse mode, mode-locked ruby laser is described. 相似文献
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《中国科学:物理学 力学 天文学(英文版)》2015,(11)
The mode and high-speed modulation characteristics are investigated for a microsquare laser with a side length of 16 ?m and a 2-?m-wide output waveguide connected to one vertex. The longitudinal and transverse mode characteristics are analyzed by numerical simulation and light ray model, and compared with the lasing spectra for the microsquare laser. Up to the fifth transverse mode is observed clearly from the lasing spectra. Single mode operation with the side mode suppression ratio of 41 d B is realized at the injection current of 24 m A, and the maximum output power of 0.53(0.18) m W coupled into the multiple(single) mode fiber is obtained at the current of 35 m A, for the microsquare laser at the temperature of 288 K. Furthermore, a flat small-signal modulation response is reached with the 3-d B bandwidth of 16.2 GHz and the resonant peak of 3.6 d B at the bias current of 34 m A. The K-factor of 0.22 ns is obtained by fitting the damping factor versus the resonant frequency, which implies a maximum intrinsic 3-d B bandwidth of 40 GHz. 相似文献