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Characteristics of a Ne-like Ar 46.9-nm soft X-ray laser in capillary discharge at a low Ar pressure
A capillary discharge-pumped Ne-like Ar 46.9-nm soft X-ray laser at a low Ar pressure (28–46 Pa) is proven. To our knowledge, this is the first time an XRD laser output in the condition of the low threshold of a main-current pulse spike (20–21 kA) is demonstrated. The Al2O3 ceramic capillary tube is 20 cm in length (Mo electrode is 4 cm in length) and 3 mm in diameter. The maximum laser energy of the precalibrated XRD is 3.5 μJ. The maximum gain coefficient g = 0.46 cm?1, the maximum gain-length product is 8.28, the beam divergence is 5.4 mrad, and the laser pulse width is 1.65 ns. In addition, the results show that the laser plasma column became difficult to Z-pinch with a increasing Ar pressure, its Z-pinching state of a higher Ar pressure fluctuates more intensely than that of a lower pressure by analyzing the scattering of the delay time between the pre-and main-current pulse. 相似文献
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Yongpeng Zhao Han Wu Yao Xie Shan Jiang Huaiyu Cui Qi Wang 《Journal of Russian Laser Research》2013,34(3):219-225
We realize a Ne-like Ar 46.9 nm soft X-ray laser pumped by a capillary discharge. The study of the laserpulse-intensity distribution is important for applications of soft X-ray lasers. The intensity distribution demonstrates the gain distribution, plasma radius, and axial plasma density that contribute to the study of the laser-pulse formation. To measure the intensity in different positions of the X-ray laser spot, we moved transversally an X-ray diode (XRD) assembled with a slit. We obtain the onedimensional intensity distribution. We find a laser divergence (FWHM) of 4.0 mrad. According to the gain-guided model, we calculate the intensity distribution. The measured divergence of 4.0 mrad roughly corresponds to a plasma radius a approximately equal to 230–250 μm and on-axis electron density n e ≈ 8.0?1018 ?9.0?1018 cm ?3. The results of calculations indicate that the divergence of the intensity distribution increases when the plasma radius decreases and the on-axis electron density increases. 相似文献
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以哈尔滨工业大学可调谐激光技术国家重点实验室中的Marx发生器的放电脉冲波形为基础,理论上模拟计算了在不同放电参数下充氩气的毛细管放电产生的等离子体状态和类氖氩离子3p_3s跃迁线的增益系数的时空演变过程。中心模型中,选取内径为3.1 mm 的陶瓷毛细管并充入初始密度为1.07×10-6g·cm-3的氩气,电流脉冲峰值为27.81 kA,脉冲宽度为61.4 ns。改变放电参数进行模拟,结果表明:上升前沿越陡,则增益系数越大,电流脉冲上升时间在20~40 ns,电流峰值在25~40 kA,电流脉冲宽度在50~70 ns范围内,毛细管放电产生的等离子体状态比较理想,可获得较高的增益系数。 相似文献
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以哈尔滨工业大学可调谐激光技术国家重点实验室中的Marx发生器的放电脉冲波形为基础,理论上模拟计算了在不同放电参数下充氩气的毛细管放电产生的等离子体状态和类氖氩离子3p_3s跃迁线的增益系数的时空演变过程。中心模型中,选取内径为3.1 mm 的陶瓷毛细管并充入初始密度为1.07×10-6g·cm-3的氩气,电流脉冲峰值为27.81 kA,脉冲宽度为61.4 ns。改变放电参数进行模拟,结果表明:上升前沿越陡,则增益系数越大,电流脉冲上升时间在20~40 ns,电流峰值在25~40 kA,电流脉冲宽度在50~70 ns范围内,毛细管放电产生的等离子体状态比较理想,可获得较高的增益系数。 相似文献
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A. Ritucci G. Tomassetti A. Reale L. Palladino L. Reale T. Limongi F. Flora L. Mezi S.V. Khuklevsky A. Faenov T. Pikuz J. Kaiser 《等离子体物理论文集》2003,43(2):88-93
A capillary discharge pumped soft x‐ray laser operating at 46.9 nm on the 3p–3s transition of the Ne‐like Ar has been realized by pumping the active medium with a relatively slow current pulse (dI/dt ≈ 6 · 1011 A/s). In order to study the role of the ablation in the production of the laser effect, the intensity of the amplified 46.9 nm line has been investigated using the same pumping current pulses in the plastic (polyacetal) and ceramic (Al2O3). We showed that the ablation of the capillary walls is unfavorable both for the compression and stability of the plasma and consequently for the soft x‐ray laser production. The amplification and lasing effects are observed only in the ceramic channel. The measurements of the line intensity at 46.9 nm showed the lasing with a gain‐length product of ≈ 9, a laser pulse energy of ≈ 5 μJ, a pulse duration of 1.3 ns and a beam divergence of ≈ 3.5 mrad. In addition, effect of the scaling of the time of lasing with the initial plasma diameter was demonstrated experimentally and compared with a one‐dimensional MHD model. 相似文献
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毛细管放电Z箍缩等离子体软X射线激光器近几年发展非常迅速,已经获得了在46.9nm的波长上近毫焦量级的激光输出,重复频率达到了4Hz.利用这种软X射线激光在等离子诊断、物质烧熔等方面已开展了初步的应用实验研究.文章介绍了毛细管放电泵浦的两种物理机制,阐述了类氖氩离子2p^53p^1S0-2p^53s^1P1能级间粒子数反转的形成及毛细管放电等离子体柱的演变过程.深入理解这些物理过程,对发展毛细管放电软X射线激光将起到积极作用。 相似文献
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M. Emami 《Laser Physics》2007,17(1):18-21
An analysis for designing capillary Z-pinch plasma as an alternative active medium of soft X-ray laser is presented. The validity of calculation results are verified by experiment. Namely, the specification of driving current as well as the predicted pinch time is in good agreement with the experimental results. This study also reveals the possibility of reducing the main charging voltage without degrading the performance of the X-ray laser. 相似文献
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在一台毛细管快放电软x射线激光实验装置上,在相同主脉冲条件下(电流峰值18—30kA,半周期80ns),通过观测放电产生的软x射线辐射,研究了该装置固有的高幅值(2—5kA)和外加的低幅值(10—20A)两种预脉冲,对聚乙烯毛细管和高纯度陶瓷毛细管(99.9%)放电的管壁烧蚀及等离子体状态的影响.采用装置固有的几kA预脉冲和聚乙烯毛细管,放电 过程中产生了大量的管壁烧蚀,并且这种情况下的等离子体均匀性差,没有可能获得激光输 出.而采用20A的预脉冲和高纯度陶瓷毛细管,管壁烧蚀量大大减少,预电离等离子体的均匀 性好,在这种情况下,实验上利用x射线二极管观测到了激光尖峰信号.
关键词:
预脉冲
毛细管放电
软x射线激光 相似文献
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A. Ritucci G. Tomassetti A. Reale L. Palladino L. Reale F. Flora L. Mezi S.V. Kukhlevsky A. Faenov T. Pikuz 《Applied physics. B, Lasers and optics》2004,78(7-8):965-969
The characterization of the laser beam intensity distribution of a highly saturated 46.9-nm soft X-ray laser excited by capillary discharges is reported. The laser produces a total output energy of 300 J/pulse by amplification in plasma channels having lengths up to 0.45 m. A regime of laser amplification, which is almost free from the effect of the refraction defocusing, is experimentally determined. This regime produces a soft X-ray laser beam with an intense sub-milliradiant component. In the longer active medium the laser intensity distribution reaches the divergence of 0.6 mrad, which approaches the limit of diffraction. A comparison of the experimental results with the simulations performed with a ray-tracing code shows that the small divergence of the beam could be attributed to the effect of a weak index waveguiding of the laser beam through the long plasma channels. PACS 42.55.Vc; 42.60.Jf 相似文献
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利用x射线二极管(XRD),实验上测量了毛细管放电激励下类氖氩469nm软x射线激光的尖 峰信号. 改变毛细管的充气气压和主脉冲放电电流,研究了激光尖峰的产生时间随实验参数 的变化情况. 实验结果表明,激光产生于主脉冲电流波形的前沿,此时的主脉冲电流是其峰 值的65%—75%. 增加毛细管充气气压或者减小主脉冲峰值电流,激光的产生时间将会稍有延 迟. 同时改变毛细管充气气压时,激光尖峰信号在42Pa存在最大值.
关键词:
毛细管放电
软x射线激光
激光产生时间 相似文献
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Ne-like Ar 46.9 nm soft X-ray laser has been realized by the main current with different rise time. In this paper, the spectrum
of capillary discharge Ne-like Ar 46.9 nm soft X-ray laser has been detected using a Rowland spectrograph, a new method of
changing the rise time of the main current is also researched when the other conditions are fixed. The rise time will be changed
when altering the inductance of the main switch, which will influence the time of lasing onset and the energy of the laser
output. The time of lasing onset will be postponed and the energy of the laser will increase when the induction of the main
switch increases. The energy of the laser increase by 78.5% when the rise time is changed from 38 to 55 ns. 相似文献
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Q. Wang Y. Xie Y. P. Zhao Q. S. Zhu M. Z. Mo D. W. Yang 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,55(1):243-247
To raise the utilization ratio of the energy power, and
meanwhile, guarantee the waveform of the main discharge current to obtain
X-ray laser, our capillary discharged Ne-like Ar soft X-ray laser system
adopts Blumleim transmission line (BTL) and a 300 kV-Marx generator; and by
using our self-developed intrinsic-prepulse elimination device and
extrinsic-prepulse generator, we successfully removed the intrinsic prepulse
of BTL, and thus eliminated its deteriorative effect towards Z-pinch plasma.
By this means, we obtained stable X-ray laser output; and the voltage
transmission rate of our system nearly reaches 122%, which provides a
guarantee for the miniaturization of the power source and the whole system. 相似文献