Yuanzhi Dong 1,2,3Yunxia Jin 1,3,4Fanyu Kong 1,3,*Jingyin Zhao 1,3[ ... ]Jianda Shao 1,2,3,4,5
Author Affiliations
Abstract
1 Thin Film Optics Laboratory, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, China
2 School of Physical Sciences, University of Science and Technology of China, Hefei, China
3 Key Laboratory of High Power Laser Materials, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, China
4 CAS Center for Excellence in Ultra-intense Laser Science, Chinese Academy of Sciences, Shanghai, China
5 Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, China
In this paper, a 2D angle amplifier based on peristrophic multiplexed volume Bragg gratings is designed and prepared, in which a calculation method is firstly proposed to optimize the number of channels to a minimum. The induction of peristrophic multiplexing reduces the performance difference in one bulk of the grating, whereas there is no need to deliberately optimize the fabrication process. It is revealed that a discrete 2D angle deflection range of ±30° is obtained and the relative diffraction efficiency of all the grating channels reaches more than 55% with a root-mean-square deviation of less than 3.4% in the same grating. The deviation of the Bragg incidence and exit angles from the expected values is less than 0.07°. It is believed that the proposed 2D angle amplifier has the potential to realize high-performance and large-angle beam steering in high-power laser beam scanning systems.
beam scanning high-power lasers volume Bragg gratings High Power Laser Science and Engineering
2023, 11(1): 01000e13
红外与激光工程
2022, 51(12): 20220239
Jingyin Zhao 1,2,3Yunxia Jin 1,3,4,*Fanyu Kong 1,3Dongbing He 1,3[ ... ]Jianda Shao 1,3,4,5
Author Affiliations
Abstract
1 Thin Film Optics Laboratory, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
2 Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
3 Key Laboratory of High Power Laser Materials, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
4 CAS Center for Excellence in Ultra-Intense Laser Science, Chinese Academy of Sciences, Shanghai 201800, China
5 Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, China
Measuring the topological charge (TC) of optical vortex beams by the edge-diffraction pattern of a single plate is proposed and demonstrated. The diffraction fringes can keep well discernible in a wide three-dimensional range in this method. The redundant fringes of the diffracted fork-shaped pattern in the near-field can determine the TC value, and the orientation of the fork tells the handedness of the vortex. The plate can be opaque or translucent, and the requirement of the translucent plate for TC measurement is analyzed. Measurement of TCs up to is experimentally demonstrated by subtracting the upper and lower fringe numbers with respect to the center of the light. The plate is easy to get, and this feasible measurement can bring great convenience and efficiency for researchers.
optical vortex orbital angular momentum topological charge measurement Chinese Optics Letters
2022, 20(11): 110501
1 1.中国科学院 上海光学精密机械研究所, 上海 201800
2 2.中国科学院大学 材料与光电研究中心, 北京 100049
对光热折变(Photo-thermal-refractive, PTR)玻璃在总剂量分别为0.35、1、10及100 kGy的γ射线下辐照, 并进行热退火处理, 采用吸收光谱、光致发光光谱及EPR电子顺磁共振谱研究了光热折变玻璃在γ射线辐照下的辐照机理。研究结果表明, γ辐照后的PTR玻璃在可见波段的吸收主要由银原子Ag0、银分子簇Ag2、银分子簇Ag3、银纳米颗粒Agm0及非桥氧空穴中心HC1及HC2引起; 在不同剂量γ射线辐照下, 玻璃基质中的变价离子(Ag+、Ce3+)价态先发生变化, 同时玻璃基质中的非桥氧键发生电离, 形成了非桥氧空穴型缺陷中心HC1、HC2。进一步增加辐照剂量, 产生了银的分子簇Ag2和Ag3; 同时玻璃基质中非桥氧空穴中心HC2的浓度增大, 导致在639 nm附近的吸收增强。分别在不同温度下对辐照后的PTR玻璃进行相同时间的热处理及在低于Tg(玻璃转变温度)的温度下进行不同时间的热处理, 观察到250 ℃退火后PTR玻璃中HC1及HC2缺陷中心发生漂白; 并在430 ℃退火后出现了银纳米颗粒的吸收峰, 该吸收峰随退火时间的延长发生了红移及展宽。
光热折变玻璃 γ射线辐照 辐照缺陷 紫外-可见吸收谱 photo-thermal-refractive glass γ-ray irradiation defect center UV-Vis absorption
1 中国科学院上海光学精密机械研究所高功率激光单元技术实验室, 上海 201800
2 中国科学院大学, 北京 100049
3 中国科学院上海光学精密机械研究所强场激光物理国家重点实验室, 上海 201800
4 上海大恒光学精密机械有限公司, 上海 201800
通过实验和理论相结合的方式,从热透镜效应角度研究了Er 3+,Yb 3+∶glass在激光二极管(LD)端面抽运条件下的激光输出能量,建立起LD抽运重复频率、Er 3+,Yb 3+∶glass热光系数与空腔运转斜率效率、调Q输出脉冲能量之间的关系。采用平凹腔结构,并以Co 2+∶MgAl2O4作为调Q开关,设计了LD端面抽运被动调Q激光器,实验结果发现,当热焦距大于前腔面光斑半径最小值对应的热焦距时,空腔运转斜率效率与材料的热光系数呈负相关,调Q输出脉冲能量与热光系数及抽运重复频率均呈负相关。基于理论研究,通过热焦距公式、稳定谐振腔的矩阵计算法以及被动调Q的速率方程进行数值模拟,解释并验证上述实验现象。结果显示,可通过降低抽运重复频率和选择低热光系数的Er 3+,Yb 3+∶glass等方式降低热透镜效应实现高脉冲能量的输出。
激光器 热透镜效应 输出能量 Er
3+ Yb
3+∶glass; 抽运重复频率 热光系数 中国激光
2021, 48(17): 1701002
红外与激光工程
2020, 49(12): 20201081
设计了一种阈值较低的太阳光直接抽运的Nd∶YAG固体激光器,采用有效面积为1.03 m
2、焦距为1.2 m的菲涅耳透镜为第1级太阳光会聚装置,分腔水冷型镀金锥形腔为第2级太阳光会聚装置。在液体导光透镜和镀金锥形腔的共同作用下,通过端面、侧面同时抽运直径为5 mm、长度为75 mm的Nd∶YAG螺纹晶体棒,获得了连续稳定的1064 nm激光输出。利用光学设计软件ZEMAX和激光谐振腔仿真软件LASCAD建立理论模型,通过数值模拟验证实验结果并优化系统设计。该太阳光抽运Nd∶YAG固体激光器的激光输出功率最高为31.5 W,收集效率为30.58 W/m
2,激光器阈值功率为102 W,斜率效率为4.25%,太阳光到激光的能量转换效率为3.2%。
激光器 太阳光抽运 Nd∶YAG; 螺纹棒 数值模拟 光学学报
2017, 37(11): 1114001
Author Affiliations
Abstract
1 Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
2 University of Chinese Academy of Sciences, Beijing 100049, China
3 Laser Fusion Research Center, Chinese Academy of Engineering Physics, Mianyang, Sichuan 621900, China
This work presents a brief introduction on three kinds of newly developed $\text{Nd}^{3+}$-doped laser glasses in Shanghai Institute of Optics and Fine Mechanics (SIOM), China. Two $\text{Nd}^{3+}$-doped phosphate glasses with lower thermal expansion coefficient and thermal shock resistance 4 times higher than that of N31 glass are developed for laser processing. Nd:Silicate and Nd:Aluminate glasses with peak emission wavelength at 1061 and 1065 nm, effective emission bandwidth of 34 and 50 nm, respectively, are developed for Exawatt-class laser system application. Fluorophosphate glasses with low nonlinear refractive index ($n_{2}=0.6{-}0.86$) and long fluorescence lifetime ($430{-}510~\unicode[STIX]{x03BC}\text{s}$) are investigated for the purpose of decreasing B integral in high-power laser system. The properties of all these glasses are presented and compared with those of commercial neodymium laser glasses.
aluminate glass fluorophosphate glass high-power laser neodymium laser glass phosphate glass silicate glass High Power Laser Science and Engineering
2017, 5(1): 010000e1
1 中国科学院上海光学精密机械研究所高功率激光单元研发中心, 上海 201800
2 中国科学院大学, 北京 100049
3 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
研究了新型掺钕磷酸盐激光玻璃在高能量闪光灯抽运条件下的热破坏性质。激光输出实验表明这种为重复频率激光工作设计的钕玻璃,具有与高峰值功率应用类型的钕玻璃基本相近的激光输出能力,高于早期设计的高能量应用类型的钕玻璃。分析了新型重频工作钕玻璃的热膨胀性质,比较了酸蚀和离子交换前后激光输出性质,测定了重复频率高能量抽运下的极限抽运阈值,并讨论了它们对于耐抽运破坏极限的影响。
材料 磷酸盐 钕玻璃 激光 重复频率 耐抽运阈值
1 中国科学院 上海光学精密机械研究所 强激光材料重点实验室,上海 201800
2 中国科学院 研究生院,北京 100049
以提高磷酸盐激光钕玻璃耐热冲击性能为目的,研究了一种用碱和酸缓冲液相结合处理磷酸盐激光钕玻璃表面的方法。通过对比该方法与303砂细磨、混合强酸处理和化学机械抛光3种方法处理后的表面形貌和机械性能,发现该表面处理方法可以减少玻璃表面的显微缺陷,从而显著提高表面显微硬度、抗折强度。实验结果表明采用该表面处理方法可提高磷酸盐激光钕玻璃在重复频率氙灯抽运下的热破坏阈值和激光效率。
材料 磷酸盐激光玻璃 表面处理方法 表面酸碱处理 表面缺陷