增益开关型四能级激光器的时间特性分析

从四能级系统的速率方程出发 ,结合实际的物理条件 ,针对极短脉冲 (10 ns)泵浦下增益开关型激光器的时间特性建立了一个简洁模型 ,得到了输出脉冲的建立时间和脉冲宽度与泵浦能量及能量密度之间的解析关系式 ,并结合实验分析了模型的合理性。     

利用超短脉冲光束实现在真空中加速电子的方案

研究了一种利用超短强激光脉冲实现在真空中加速自由电子的方案，并讨论了其具体实施的可行性。同时给出了实现该方案的计算机模拟结果，与理论分析很好地符合。结果表明该方案简易可行，具有很高的实用价值。     

短脉冲泵浦类锂铝离子X射线激光模拟

建立了适合描述短脉冲激光泵浦类Ｌｉ离子产生Ｘ射线激光的简化流体和原子动力学模型。短脉冲激光泵浦纤维靶产生等离子体的电子密度、电子温度、电离态分布等和驱动激光功率密度、脉宽及纤维靶半径相联系。研究了类Ｌｉ铝离子４ｆ－３ｄ跃迁激光增益系数随时间的演化过程，以及峰值增益和泵浦激光功率、脉宽及纤维靶半径之间的关系。     

飞秒激光在铌酸锂内部的电光集成

近年来,飞秒激光由于其超快时间特性和超高峰值功率特性在精密微纳加工领域引起了人们极人的兴趣.利用飞秒激光在透明材料内部实现微光学、微电子、微流体等多功能的集成得到越来越多的重视[1-3].     

Interactions of a Femtosecond Intense Laser with Rare Gas Clusters in a Dense Jet

A study on the interactions of high intensity (- 10^16 W/cm^2) femtosecond laser pulses with rare gas clusters in a dense jet is performed. Energy absorption by Ar and Xe clusters is measured and it can be as high as 90%. Very energetic ions produced in the laser interaction with a dense cluster jet are detected by time-of-flight spectrometry and the maximum ion energy of Xe is up to 1.3 MeV. The average ion energies are found to increase with increasing cluster size and get saturated gradually. The average ion energies also show a strong directionality and the average ion energy in the direction parallel to the laser polarization vector is 40% higher than that perpendicular to it. The findings are discussed in terms of a model of charge-dependent ion acceleration.     

开放V型系统产生无反转激光的两类时间演化

从旋波、慢变振幅及平均场近似下的密度矩阵运动方程出发,利用数值计算结果研究了开放的V型三能级系统在共振条件下通过Pitchfork分岔产生的连续波无反转激光(LWI)场和通过Hopf分岔产生的自脉动LWI场及相应的各能级粒子数布居的时间演化规律,讨论了系统各参量变化对此时间演化规律的影响。     

Demonstration of X-ray Thomson Scattering on Shenguang-Ⅱ Laser Facility

X-ray Thomson scattering technique for diagnosing dense plasma was demonstrated on Shenguang-Π laser facility.Laser plasma x-ray source of titanium He-α lines (～4.75keV),generated by laser beam (1.5kJ/527nm/2ns) heated titanium thin foil,was used as x-ray probe beam.The x-ray probe was then scattered by cold CH foam column of 1g/cm3 density.The scattered radiation at 90 was diffracted by polyethylene terephthalate (PET) crystal and recorded on x-ray charge-coupled device.Well-defined scattering spectra were obtained with good signal to noise ratio.     

蒸发激光和载气强度对C_n~-质谱特征的影响

用激光蒸发石墨靶棒 ,脉冲载气 (carriergas)冷却的方法产生碳团簇 ,由飞行时间质谱仪测得碳团簇负离子的飞行时间质谱。通过对质谱的研究 ,揭示出随着尺寸的增长 ,碳团簇的结构由环状为主变为由笼状占大多数。进一步讨论了脉冲气体与蒸发激光的强弱对实验结果的影响     

超短脉冲高斯光束经聚焦透镜的光场形式

考虑到激光腔模中光腰的频率依赖性 ,得到了超短脉冲高斯光束经消色差透镜聚焦后光场的解析形式 ,并讨论了此时透镜群速度色散对光束聚焦性质的影响。分析了单透镜色差和群速度色散对超短脉冲高斯光束聚焦的时间分布及脉冲波面的影响 ;比较了消色差透镜及单透镜中脉冲初始光腰尺寸对聚焦的影响。