Author Affiliations
Abstract
1 Department of Electrical Engineering and Computer Science, Ningbo University, Ningbo 315211, China
2 Centre for Optical and Electromagnetic Research, College of Optical Science and Engineering, Zhejiang University, Hangzhou 310058, China
Mode splitters that directly separate modes without changing their orders are highly promising to improve the flexibility of the mode-division multiplexing systems. In this paper, we design a high-performance mode splitter on the silicon-on-insulator platform with a compact footprint of 14 µm× 2.5 µm using an inverse design method based on shape optimization. The fabrication of this mode splitter requires only a single lithography step and exhibits good fabrication tolerances. The experimental results show that the proposed device exhibits state-of-the-art insertion loss (<0.9 dB) and cross talk (<-16 dB) over a broad bandwidth (1500–1600 nm). Furthermore, the shape optimization method used is implemented to design a dual-mode (de)multiplexer, and the experimental results fulfill the design objective, demonstrating the excellent generality of the design method in this paper.
integrated optics inverse design mode splitter Chinese Optics Letters
2024, 22(1): 011302
长春理工大学 物理学院 吉林省固体激光技术与应用重点实验室,吉林 长春 130022
提出了一种基于1064 nm掺镱光纤激光器泵浦MgO:PPLN的3.83 μm中红外光学参量振荡器。基于单谐振光学参量振荡器的阈值理论和线宽压窄前后的光束能量集中性理论,分析了不同泵浦光束聚焦深度下,谐振腔内光束分布情况以及线宽调制前后能量的不同集中程度对阈值和光-光转换效率所产生的影响。通过采用单个光纤布拉格光栅的方式压窄了泵浦光线宽,对比分析了在不同占空比下,泵浦光线宽压窄前后对中红外光学参量振荡器输出特性的影响。当泵浦功率为18 W,脉冲激光占空比为0.2%,脉宽为100 ns,泵浦光线宽为2.5 nm时,MgO:PPLN中红外光学参量振荡器获得功率为1.42 W的3.83 μm激光输出,光-光转换效率为7.9%。将线宽压窄到0.1 nm后,脉宽为2 ns,MgO:PPLN中红外光学参量振荡器获得最高功率为1.98 W的3.83 μm激光输出,光-光转换效率为11%,光束质量M2=1.89;同时相比于线宽压窄前激光输出效率提高了39.2%。
光学参量振荡器 窄线宽 光纤激光器 中红外 占空比 optical parametric oscillatoin narrow linewidth fiber laser mid-infrared duty cycle 红外与激光工程
2022, 51(9): 20210898
红外与激光工程
2021, 50(11): 20210084
强激光与粒子束
2021, 33(7): 073010
Author Affiliations
Abstract
1 Jilin Key Laboratory of Solid Laser Technology and Application, School of Science, Changchun University of Science and Technology, Changchun 130022, China
2 Institute for Advanced Interdisciplinary Research, University of Jinan, Jinan 250022, China
We examined a 1514 nm eye-safe passively Q-switched self-optical parametric oscillator. The nonlinear crystal is an a-cut Nd:MgO:PPLN crystal, and the size of the crystal was 6 mm × 2 mm × 30 mm with 0.4 at.% Nd3+ doped and a grating period of 29.8 μm. When the crystal absorbed 12.8 W, the output maximum single-pulse energy reached 39 μJ, and a pulse width of 6.1 ns at a repetition rate of 5.4 kHz was obtained. The peak power was 6 kW, giving a slope efficiency of 42%.
140.3540 Lasers, Q-switched 190.4970 Parametric oscillators and amplifiers 140.3480 Lasers, diode-pumped 140.3460 Lasers Chinese Optics Letters
2019, 17(11): 111404
1 长春理工大学 理学院 吉林省固体激光技术与应用重点实验室, 吉林 长春 130022
2 长春高新技术产业开发区管委会, 吉林 长春 130012
报道了一种由波长锁定878.6 nm LD双端抽运Nd:YVO4声光调Q激光器, 重复频率在500 kHz时具有稳定的1 064 nm脉冲激光输出。在重频为100 kHz, 晶体吸收功率58 W时, 获得18.2 W的1 064 nm激光输出, 光-光转换效率为31.3%, 脉宽为15.2 ns; 在重频为500 kHz、晶体吸收功率58 W时, 获得26.1 W的1 064 nm激光输出, 光-光转换效率为45%, 脉宽为44.2 ns, 重频在100~500 kHz下具有稳定的脉冲输出, 光束质量较传统模式下有明显提高, 并且转换效率也有提升。实验表明: 利用波长锁定878.6 nm激光二极管直接泵浦的方式, 有利于降低晶体热效应、提高光束质量, 提高光-光转换效率, 获得窄脉宽的脉冲激光输出,并且在一定的温度变化范围内具有极好的温度稳定性。
波长锁定878.6 nm双端泵浦 Nd:YVO4晶体 低热效应 dual-end pumped wave-locked 878.6 nm Nd:YVO4 crystal low thermal effect 500 kHz 500 kHz 红外与激光工程
2018, 47(6): 0606001
西北核技术研究所激光与物质相互作用国家重点实验室, 陕西 西安 710024
复合材料的抗激光烧蚀性能一般用烧蚀单位质量所需的激光能量(即烧蚀热)表征,这种表征方式忽略了激光强度与稳定性的影响。以C/SiC复合材料为例,在材料表面热化学平衡分析的基础上,基于复合材料激光烧蚀效应数值模拟程序,计算了不同参数下激光辐照复合材料的烧蚀热,分析了强度、频率、占空比等激光参数对烧蚀效率的影响。研究结果表明,烧蚀热与占空比、激光强度有关,与重复频率关系不大。激光强度越大,烧蚀热越小;占空比减小,单位烧蚀质量所需的能量增大,即烧蚀热随占空比的减小而增大;在平均功率密度及占空比相同的前提下,不同重复频率对加热影响很小。对C/SiC复合材料的激光烧蚀,相同平均功率密度下,激光强度不稳定性越大,烧蚀热的期望值越小。
激光技术 烧蚀热 C/SiC复合材料 激光参数 不稳定性 中国激光
2013, 40(11): 1103010