Author Affiliations
Abstract
1 School of Physical Sciences, University of Science and Technology of China, Hefei 230026, China
2 Key Laboratory of High Power Laser and Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
3 National Laboratory on High Power Laser and Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
4 University of Chinese Academy of Sciences, Beijing 100049, China
The self-focusing phenomenon of partially coherent beams (PCBs) was simulated using the complex screen method combined with the split-step Fourier method to solve the nonlinear Schrödinger equation. Considering the propagation of Gaussian Schell-model beams in a nonlinear medium as an example, the suppression effects of intensity, propagation distance, and spatial coherence on small-scale self-focusing were demonstrated. Simulations of overall and small-scale self-focusing using this method were compared with the existing literature to demonstrate the validity of the method. This method can numerically analyze the degree of self-focusing in PCBs and advance the study of their nonlinearity.
partially coherent beams self-focusing nonlinearity complex screen method Gaussian Schell-model Chinese Optics Letters
2023, 21(7): 071901
中国科学院上海光学精密机械研究所高功率激光物理联合实验室，上海 201800
高功率激光装置是一个复杂的有源巨型光学工程，其性能指标要求逼近科学技术与物理极限。驱动器研制有物理设计、工程光学和结构工程设计三大过程，工程光学在其中起着重要作用。高功率激光装置工程光学设计需遵循其特有的设计原则和要点，以保证装置的高性能。根据驱动器设计指标和设计特点，从总体光学设计、光束质量控制以及光束打靶精度控制方面，综述了高功率激光装置工程光学设计中的关键科学技术问题以及相应解决方法，为未来高功率激光驱动器的发展提供必要的工程设计参考。
光学设计 惯性约束聚变 神光装置 工程光学 激光光学
1 华侨大学 土木工程学院, 福建 厦门 361021
2 福建省智慧基础设施与监测重点实验室(华侨大学）, 福建 厦门 361021
3 中建二局第一建筑工程有限公司, 广东 深圳 518003
4 西安交通大学 电子与信息学部电子科学与工程学院, 陕西 西安710049
钢管混凝土结构在超高层建筑中的应用日益广泛, 由于施工质量控制不到位及混凝土材料收缩等原因, 其内部可能出现核心混凝土空洞缺陷及混凝土与钢管壁间的界面剥离缺陷, 进而对其力学性能带来负面影响。该文针对矩形钢管混凝土截面的缺陷检测, 在表面粘贴压电陶瓷片进行测量, 对这两种内部缺陷在不同测试路径上压电陶瓷片响应的影响进行试验和数值模拟分析。通过对健康、存在核心混凝土空洞和界面剥离缺陷的不同试件不同检测路径上压电传感器输出信号的比较, 研究了缺陷对应力波传播的影响, 并得到采用对测方式检测的敏感范围。结果表明采用对测方法可有效检测钢管混凝土缺陷, 其敏感范围的确定具有工程意义。
钢管混凝土结构 界面剥离 核心混凝土缺陷 无损检测 压电陶瓷 敏感范围 concrete-filled steel tube structure interface debonding concrete core defects non-destructive testing piezoelectric ceramics sensing range
1 华侨大学 土木工程学院, 福建 厦门 361021
2 福建省智慧基础设施与监测重点实验室(华侨大学）, 福建 厦门 361021
3 中建二局第一建筑工程有限公司, 广东 深圳 518003
4 西安交通大学 电子与信息学部, 陕西 西安 710049
套筒灌浆连接是当前装配式建筑中受力钢筋的主要连接方式, 其灌浆质量是影响装配式混凝土结构性能的关键因素之一。运用压电陶瓷材料的驱动和传感功能, 该文提出了一种基于波动分析的套筒灌浆缺陷主动检测方法, 并通过试验验证其可行性, 通过数值模拟分析其机理。在套筒连接钢筋表面粘贴压电片, 测量健康试件和设置有不同尺寸缺陷试件上压电陶瓷传感器的输出信号, 并对小波包能量进行分析和比较。结果表明, 灌浆缺陷导致压电陶瓷传感器输出信号的电压幅值增大, 小波包能量指标与套筒灌浆缺陷尺寸大小相关。该法能对套筒内灌浆缺陷进行有效检测。
装配式钢筋混凝土结构 套筒灌浆缺陷 压电陶瓷 波动测量 小波包能量 试验研究 prefabricated reinforced concrete structures sleeve grouting defects piezeoelectric ceramics stress wave measurement wavelet packet energy experimental study
Author Affiliations
Abstract
1 National Laboratory on High Power Laser and Physics, Shanghai 201800, China
2 Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
3 Shanghai Institute of Laser Plasma, Chinese Academy of Engineering and Physics, Shanghai 201800, China
In this paper, we review the status of the multifunctional experimental platform at the National Laboratory of High Power Laser and Physics (NLHPLP). The platform, including the SG-II laser facility, SG-II 9th beam, SG-II upgrade (SG-II UP) facility, and SG-II 5 PW facility, is operational and available for interested scientists studying inertial confinement fusion (ICF) and a broad range of high-energy-density physics. These facilities can provide important experimental capabilities by combining different pulse widths of nanosecond, picosecond, and femtosecond scales. In addition, the SG-II UP facility, consisting of a single petawatt system and an eight-beam nanosecond system, is introduced including several laser technologies that have been developed to ensure the performance of the facility. Recent developments of the SG-II 5 PW facility are also presented.
high-power laser facility inertial confinement fusion solid-state amplifier High Power Laser Science and Engineering
2018, 6(4): 04000e55
Author Affiliations
Abstract
1 National Laboratory on High Power Laser and Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
2 Shanghai Institute of Laser Plasmas, Shanghai 201800, China
Flat-topped beam theoretical model and unified theory of coherence and polarization of light are used as the bases in examining aberrated, partially coherent, electromagnetic, square, flat-topped pulsed beams focused by a thin lens. This study demonstrates that Astigmatism is not necessarily undesirable in certain circumstances, and a certain amount of astigmatism can be guaranteed a similar spatial envelope of the beams in the geometric focal plane as the source of aberrated, partially coherent, electromagnetic, square, flat-topped pulsed beams. This feature may be useful in determining the fidelity of high-power laser-beam transmission areas.
140.3295 Laser beam characterization 140.3430 Laser theory 260.1960 Diffraction theory 260.2110 Electromagnetic optics Collection Of theses on high power laser and plasma physics
2014, 12(1): S11401
Author Affiliations
Abstract
1 National Laboratory on High Power Laser and Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
2 Shanghai Institute of Laser Plasmas, Shanghai 201800, China
To study how laser pulse wavelength will affect the damage characteristics of optical elements with different degrees of contamination, we compare the extent of damage on optical glass between nanosecond pulsed laser of 1064 and 355 nm wavelength, respectively, and reach the following conclusions: the surface quality of clean optical elements determines its own anti-laser damage capability; the damage probability of optical sample caused by ultraviolet radiation-induced organic contamination is much higher than the infrared radiation-induced one; and contaminated metal particles can lower damage threshold of optical elements by 2–3 times.
140.3390 Laser materials processing 140.3440 Laser-induced breakdown 140.6810 Thermal effects 160.3380 Laser materials 160.6030 Silica Chinese Optics Letters
2014, 12(s2): S21409
Author Affiliations
Abstract
1 National Laboratory on High Power Laser and Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
2 Shanghai Institute of Laser Plasmas, Shanghai 201800, China
Flat-topped beam theoretical model and unified theory of coherence and polarization of light are used as the bases in examining aberrated, partially coherent, electromagnetic, square, flat-topped pulsed beams focused by a thin lens. This study demonstrates that Astigmatism is not necessarily undesirable in certain circumstances, and a certain amount of astigmatism can be guaranteed a similar spatial envelope of the beams in the geometric focal plane as the source of aberrated, partially coherent, electromagnetic, square, flat-topped pulsed beams. This feature may be useful in determining the fidelity of high-power laser-beam transmission areas.
140.3295 Laser beam characterization 140.3430 Laser theory 260.1960 Diffraction theory 260.2110 Electromagnetic optics Chinese Optics Letters
2014, 12(s1): S11401
中国科学院上海光学精密机械研究所高功率激光物理国家实验室， 上海 201800
采用一台输出波长为1064 nm的NdYAG调Q激光器，以不同辐照方式对光学元件表面污染物引起的损伤开展了系统的实验研究。在确定了K9 玻璃和熔石英元件基板零几率损伤阈值的基础上，针对金属粒子污染物和有机污染物分别进行了元件损伤特性实验研究，分析了表面污染物造成元件损伤阈值下降的诱导机理。
激光光学 激光损伤 金属粒子污染 有机污染 损伤阈值 中国激光
2014, 41(s1): s102006
Author Affiliations
Abstract
1 Fujian Provincial Key Laboratory of Light Propagation and Transformation, College of Information Science & Engineering, Huaqiao University, Xiamen 361021, China
2 National Laboratory on High Power Laser and Physics Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Qinghe Road, Jiading District 390, Shanghai 201800, China
The intensity distributions of a high-power broadband laser beam passing through a nonlinear optical medium with defects and then propagating in free space are investigated based on the general nonlinear Schr?dinger equation and the split-step Fourier numerical method. The influences of the bandwidth of the laser beam, the thickness of the medium, and the defects on the light intensity distribution are revealed. We find that the nonlinear optical effect can be suppressed and that the uniformity of the beam can be improved for a high-power broadband laser beam with appropriate wide bandwidth. It is also found that, under the same incident light intensity, a thicker medium will lead to a stronger self-focusing intensity, and that the influence of defects in the optical elements on the intensity is stronger for a narrowband beam than for a broadband beam.
broadband laser beam defects nonlinear medium self-focusing High Power Laser Science and Engineering
2013, 1(3-4): 3-43-4000132
