共查询到18条相似文献,搜索用时 125 毫秒
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毛细管放电条件下类氖序列原子参量计算与分析 总被引:2,自引:0,他引:2
利用多组态求解相对论性的Hartree-Fock-Roothan方程(HFR)方法计算了类氖离子(Z=13~27)2s^22p^5—2s^22p^53s能级之间跃迁的原子参量,包括类氖氩激光系统的能级,振子强度,自发辐射衰变速率,能级寿命,电子碰撞激发截面及电子碰撞激发速率系数等。以类氖氩离子为例,分析了等离子体内46.9nm激光跃迁的粒子数反转的形成及谱线放大过程,讨论了其它几条谱线产生增益的可能性,分析了激光线振子强度随核电荷数的变化规律。根据获得的原子参量,计算了利用毛细管放电产生类氖氩和类氖氪x射线激光的放电参量,其中类氖氩毛细管放电的初始压强的范围为30~90Pa,放电电流峰值为10~50kA。理论计算结果为类氖氩x光激光实验分析,深入研究等离子体反转动力学,激光增益的估算及理论方案设计等提供了基本数据。 相似文献
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纳秒量级激光驱动的类氖锗软X射线激光具有出光稳定和输出强度大等优点,在诸多领域拥有很好的应用价值. 研究了通过在光路中增加一块多层膜反射镜实现双程放大对出光特性的影响. 通过估算和实验,证实了增加反射镜双程放大确实能够提高类氖锗软X射线激光的输出强度,对于24mm的双程放大长度,总输出强度会增加约2.3倍. 但同时这种模式也带来了光束质量的下降,对应用研究并非完全有益.
关键词:
软X射线激光
反射镜双程放大
增益饱和 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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为了获得较窄增益带宽、较大光强的太赫兹辐射,尝试了利用TEA CO2激光器对6 W可调谐连续波CO2种子激光实行双程光放大实验,以期望获得长脉冲、高峰值功率的抽运光.通过实验,获得了大约30倍的放大系数,放大光输出功率随种子光注入功率的增加而增加,其中10 P (20)支线表现更加突出,并且被放大的激光支线半峰全宽在14 μs左右.基于这种长脉冲抽运源,建立了一种产生脉冲太赫兹的动力学模型,给出了产生太赫兹辐射的饱和抽运光强表达式,确定了抽运光的光强范围.另外,
关键词:
激光物理
长脉冲
动力学模型
太赫兹激光 相似文献
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王淑平 《中国光学与应用光学文摘》2006,(1)
O434.1∥TN2412006010785毛细管放电抽运软X光激光产生条件的实验研究=Ex-peri mental investigation of lasing condition for soft X-raylaser pumped by capillary discharge[刊,中]/栾伯晗(哈尔滨工业大学可调谐激光技术国家级重点实验室.黑龙江,哈尔滨(150001)),赵永蓬…∥中国激光.—2005,32(9).—1189-1192实验探索了较低氩气气压下激光产生的条件,利用X射线二极管(XRD)测量了毛细管放电激励类氖氩46.9nm软X光激光的输出。在其他实验参量不变的情况下,改变主脉冲电流的波形,比较了激光尖峰与背景光的相对位置。实验结果表明,当… 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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建立了计算69.8nm激光增益系数的理论模型,根据实验参数,计算了在主脉冲电流为12 kA时,69.8nm激光增益系数最大值为0.32 cm~(-1).理论模拟了不同初始气压下增益系数在毛细管径向上的分布情况.对理论结果的分析表明,最佳的初始气压在12—14 Pa范围内,此时69.8nm激光增益系数的极值最大.实验上,利用毛细管放电装置和罗兰光谱仪,测量了不同气压下的69.8nm激光强度,实验确定的最佳气压为16 Pa,与理论结果相近.此外,实验测量的增益系数(0.4 cm~(-1))略高于理论计算的增益系数(0.32 cm~(-1)). 相似文献
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The demonstration of a 69.8?nm laser on 3p 3P2 - 3s 1P1 (J=2-1) transition of Ne-like Ar pumped by capillary discharge is reported in this Letter. A main current of 12?kA with rise time of 43?ns was chosen to generate the plasma in a 35?cm long capillary filling with pressure of Ar as low as 11?Pa, resulting in a gain coefficient of 0.34?cm(-1) and gain-length product of 11 at 69.8?nm. Also observed is a weak laser on 3p 3D2 - 3s 3P1 (J=2-1) transition of Ne-like Ar at 72.6?nm in the same condition. In addition, multiwavelength lasing at 46.9, 69.8, and 72.6?nm was simultaneously realized in a capillary discharge plasma column, conditioning the pressure of Ar to 13?Pa. 相似文献
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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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G. Tomassetti A. Ritucci A. Reale L. Palladino L. Reale S. V. Kukhlevsky F. Flora L. Mezi J. Kaiser A. Faenov T. Pikuz 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,19(1):73-77
A capillary discharge soft X-ray laser operating at 46.9 nm on the transition 3p-3s (J = 0-1) of the Ne-like Ar has been realized by exciting the active medium with a long half-cycle duration current pulse of
140 ns. The current is produced by discharging a 10 nF water dielectric capacitor, initially charged to voltages lower than
200 kV by a six stage Marx generator, through a 15-cm long capillary channels. The laser amplification has been obtained by
properly adjusting all the other experimental parameters. Utilizing a 3-mm in diameter Al2O3 capillary channel initially filled with 0.3 torr of Ar pressure, a laser beam, which has a 4-mrad divergence and a time duration
of 1.3 ns, is characterized by a gain of 0.6±0.1 cm-1. The stability of the plasma compression followed by the laser emission is verified.
Received 13 December 2001 相似文献
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研究了不同条件下脉冲放电CO2激光烧蚀平板锡靶产生的等离子体极紫外辐射特性, 设计并建立了一套掠入射极紫外平焦场光栅光谱仪, 结合X射线CCD探测了光源在6.5~16.8 nm波段的时间积分辐射光谱,得到了极紫外光谱随激光脉宽, 入射脉冲能量及背景气压的变化规律。实验结果发现:入射激光脉冲能量在30~600 mJ变化时,极紫外辐射光谱的强度随辐照激光脉冲能量的增加而增加, 但并不是线性关系, 具有饱和效应, 且产生极紫外辐射的脉冲能量阈值约为30 mJ,当激光脉冲能量为425 mJ时具有最高的转换效率,此时中心波长13.5 nm处2%带宽内的转换效率约为1.2%。激光脉冲半高全宽在50~120 ns范围内变化时, 极紫外辐射光谱的峰值位置均位于13.5 nm,光谱形状几乎没有什么变化, 但是脉宽从120 ns变到52 ns后,由于激光功率密度的提高,极紫外辐射强度也随之增强了约1.6倍。极紫外光谱的强度随背景气压的增大而迅速下降, 当腔内空气气压为200 Pa时, 极紫外辐射光子几乎被全部吸收,而当缓冲氦气气压为7×104 Pa时,仍能够探测到微弱的极紫外辐射信号,计算表明100 Pa的空气对13.5 nm极紫外光的吸收系数为3.0 m-1,而100 Pa的He气的吸收系数为0.96 m-1。 相似文献
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报道了毛细管放电69.8 nm软X射线激光的光强分布特性. 实验中所用毛细管长度为35 cm, 放电主脉冲电流幅值为11.5 kA, 放电初始气压为14-16 Pa. 测得的光斑强度分布由两部分构成, 在中心有一个占光强绝大部分的主峰, 其发散角约为0.4 mrad, 边缘还有两个小的离轴峰, 峰-峰发散角约为1.5 mrad. 理论上采用几何光学近似的方法对其光强分布进行计算, 光斑如此小的发散角主峰的出现, 可能主要是由于毛细管放电过程中电子密度在轴心处具有轻微凹陷造成的. 相似文献
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Generation of millijoule-level soft-x-ray laser pulses at a 4-Hz repetition rate in a highly saturated tabletop capillary discharge amplifier 总被引:17,自引:0,他引:17
Laser pulses with energies of as much as 1 mJ were generated at a wavelength of 46.9 nm by single-pass amplification in a 34.5 cm-long Ne-like Ar capillary discharge plasma. The large gain-length product of this plasma column allows for soft-x-ray amplification in a highly saturated regime, resulting in efficient energy extraction. Average laser output pulse energy of 0.88 mJ and peak power of 0.6 MW were obtained at a repetition rate of 4 Hz. With an estimated peak spectral brightness of approximately 1x10(23)photons /(s mm(2)mrad> (2)0.01% bandwidth) this tabletop laser is one of the brightest soft-x-ray sources to date. 相似文献
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Operation and output pulse characteristics of an extremely compact capillary-discharge tabletop soft-x-ray laser 总被引:3,自引:0,他引:3
We report on the operating parameters and laser output pulse characteristics of an extremely compact discharge-pumped 46.9-nm laser of a size comparable with that of many widely utilized visible and ultraviolet gas lasers. This capillary-discharge laser generated subnanosecond laser pulses with energies of as much as 25microJ by single-pass amplification in an 18.6-cm-long argon-plasma column. Measurements of the laser output energy, pulse width, far-field beam profile, and beam divergence are reported. 相似文献