【摘 要】
:
An investigation of the cluster size dependence of the maximum energy of protons ejected from explosion of methane clusters in an intense femtosecond laser field has been conducted on the basis of the cluster size estimation by Rayleigh scattering measure
【机 构】
:
StateKeyLaboratoryofHighFieldLaserPhysics,ShanghaiInstituteofOpticsandFineMechanics,ChineseAcademyof
【出 处】
:
ChineseOpticsLetters
论文部分内容阅读
An investigation of the cluster size dependence of the maximum energy of protons ejected from explosion of methane clusters in an intense femtosecond laser field has been conducted on the basis of the cluster size estimation by Rayleigh scattering measurements. The interaction of a 2*10^(16)-W/cm2 intense laser pulse (790 nm, 60 fs) with the methane clusters revealed that the clusters were Coulomb exploded and the maximum energy (E_(max)) of the protons produced was linearly proportional to the square of the cluster radius (r_(c)^(2)). In a cluster size range, with the methane cluster radii up to about 3 nm, the established relation of E_(max) and r_(c)^(2) was found to be E_(max) (keV) = 3.3 0.75r_(c)^(2) (nm2), in good agreement with the simulation results. This demonstrated that Coulomb explosion of ionic clusters (C^( 4)H^( )_(4))_(n) took place following the cluster vertical ionization in the laser-cluster interaction.
其他文献
美国惯性聚变计划在发展惯性聚变技术上有着双重目的。近期目的是武器物理应用,远期目的是演示商用能源的可行性。聚变计划的部署是完成三个驱动器装置的建造。ANTARES(1983财年底)、NOVA(1984财年底)和PBFAII(1986财年初),以及分别用CO2、玻璃激光(频率转换)和脉冲源(离子束)诸途径进行实验。实验的目的是进一步获得基本物理数据和弄清预定1987财年期间进行点火的要求。
研制出一台全固态低噪声连续单频Nd∶YVO4-LBO双波长激光器,通过优化三硼酸锂(LBO)的匹配温度,获得了波长为1.06 μm的激光功率为3.8 W、波长为532 nm的激光功率为7.8 W的连续单频双波长激光输出,并有效降低双波长激光的强度噪声和相位噪声。实测的1.06 μm和532 nm波长激光的强度噪声均在分析频率大于3.5 MHz时达到散粒噪声极限,相位噪声均在分析频率大于5 MHz时达到散粒噪声极限。当采用Pound-Drever-Hall锁腔技术锁定激光器的腔长时,1
近十几年来在软X射线波段光学中取得的进展,很大程度上与法向入射多层干涉反射镜的出现有关[1,2]。这些反射镜通常由两种介电常数不同的物质的交替层组成。理论分析表明,为了获得最大反射率,其中一种物质的吸收应尽可能小[3~5]。
在45#钢基体上以TH-2激光合金化专用粉进行激光合金化处理,通过扫描电镜动态原位观察裂纹从基体向激光合金化区(LAZ)扩展的过程,研究了疲劳裂纹扩展速率与应力强度因子幅(SIFR)的关系,分析了疲劳断口形貌和表面裂纹扩展路径的组织形态。经历一定循环次数之后,激光合金化区内部也出现裂纹,但是合金化区的边界能强烈阻滞裂纹的扩展,一旦基体中的裂纹与合金化区中的裂纹汇合,裂纹失稳扩展。裂纹扩展速率与应力强度因子幅之间的关系不满足传统的Paris公式,裂纹在基体中扩展的断口形貌有典型的疲劳辉纹,而合金化区的断口呈
本文给出了合成波长的一般计算公式和各级合成波长的测量方程组,介绍了用3.3922μm和3.3912μm双谱线He-Ne激光器产生两级合成波长体系的方法和有关实验结果。提出了两个合成波长干涉测量方案,适用于几米到100米的大尺寸测量,精度优于10~(-6)~10~(-7)。
Statistical models combined with the local plasma frequency approach applied to the atomic electron density are employed to study the photoionization cross-section for complex atoms. It is demonstrated that the Thomas–Fermi atom provides surprisingly good
研究了电磁感应透明介质中高阶非线性效应对光孤子传输的影响。采用半经典理论获得介质对光场的线性和非线性响应,基于介质特性利用波动理论推演出三-五阶非线性薛定谔方程。介质的线性非线性特性分别决定了群速度色散参量,三阶和五阶非线性系数。研究结果表明,该非线性介质既可以诱导亮孤子也可以诱导暗孤子,取决于群速度色散参量和三阶非线性系数。当前者为负同时后者为正时产生亮孤子,当两者均为负时产生暗孤子,二者可以通过载频与相应跃迁能级失谐的调节获得。与普通非线性薛定谔方程相比,三-五阶非线性薛定谔方程对亮孤子和暗孤子出现的
Polarization-dependent gain (PDG) and state of polarization (SOP) of the output signal light in Yb^(3 -) doped fiber amplifiers are studied by numerically stimulation, which showed that PDG of output signal light is not only changed with the input pump po
Elastic lidar observations of profiles of the aerosol extinction, backscattering coefficients, and the lidar ratio have been performed in Beijing. The elastic lidar transmitts wavelengths of 532 and 355 nm. The measurement altitude can reach up to 6 km. T