1 北京理工大学光电学院，北京 100081
2 中国科学院西安光学精密机械研究所，陕西 西安 710119
The empirical findings from this study confirm the superiority of reinforcement learning in formulating effective stray light suppression measures for space gravitational wave detection telescope systems. The approach not only achieves superior suppression outcomes but also introduces an efficient, flexible, and innovative solution to the challenges of stray light in space gravitational wave detection and other high-precision optical systems.
引力波 星载望远镜 杂光抑制 强化学习 gravitational wave spaceborne telescope stray light suppression reinforcement learning
1 桂林电子科技大学，广西 桂林 541004
2 中国科学院安徽光学精密机械研究所，安徽 合肥 230031
3 广西光电信息处理重点实验室，广西 桂林 541004
为了减小在提取目标偏振信息时器件参数偏差引起的误差，需要对器件参数进行检测标定。提出了通过Savart棱镜的分光成像实验对Savart棱镜的参数进行了标定的方法。基于分振幅偏振相机进行仿真，使用计算结构相似度和最小二乘拟合法对解调效果进行定量分析。通过偏振成像实验对不同偏振状态下的解调图进行了对比。分析了参数误差对不同Stokes分量的影响并验证了参数标定方法的有效性。
成像系统 偏振成像 分光棱镜 参数标定 频域解调 光学学报
2022, 42(21): 2111001
1 上海大学 材料科学与工程学院，上海 200444
2 中国科学院苏州纳米技术与纳米仿生研究所，江苏 苏州 215123
Ge2Sb1.5Bi0.5Te5薄膜具有宽光谱吸收和高稳定性的特点。在金镜上采用磁控溅射制备了40 nm厚的Ge2Sb1.5Bi0.5Te5薄膜，将其在150 ℃下退火20 min，退火后Ge2Sb1.5Bi0.5Te5由非晶态转变为晶态。测试发现晶态Ge2Sb1.5Bi0.5Te5可饱和吸收体的调制深度提高到了原来的1.4倍，基于晶态Ge2Sb1.5Bi0.5Te5可饱和吸收体实现了脉冲宽度为1.52 ps、信噪比为47 dB的光纤锁模激光器。制备了40、60、80 nm的Ge2Sb1.5Bi0.5Te5薄膜，分析表明，随着Ge2Sb1.5Bi0.5Te5薄膜厚度的增加，光吸收率明显增加，这说明Ge2Sb1.5Bi0.5Te5薄膜的光学性质具有可控性，Ge2Sb1.5Bi0.5Te5材料在超快激光器中有应用潜力。
Ge2Sb1.5Bi0.5Te5 可饱和吸收体 锁模 掺铒 光纤激光器 退火 Ge2Sb1.5Bi0.5Te5 Saturable absorber Mode-locked Erbium-doped Fiber lasers Anneal
Author Affiliations
Abstract
1 Key Laboratory of 3D Micro/Nano Fabrication and Characterization of Zhejiang Province, School of Engineering, Westlake University, 18 Shilongshan Road, Hangzhou, 310024 Zhejiang Province, China
2 Institute of Advanced Technology, Westlake Institute for Advanced Study, 18 Shilongshan Road, Hangzhou, 310024 Zhejiang Province, China
Computer-generated holography can obtain the wavefront required for constructing arbitrary intensity distributions in space. Currently, speckle noises in holography remain an issue for most computational methods. In addition, there lacks a multiplexing technology by which images from a single hologram and light source can be switched by a lens. In this work, we first come up with a new algorithm to generate holograms to project smoother images by wavevector filtering. Thereupon, we propose a unique multiplexing scheme enabled by a Fourier lens, as the incident light can be decomposed either by a superposition of spherical waves or plane waves. Different images are obtained experimentally in the spatial and wavevector domains, switchable by a lens. The embedded wavevector filtering algorithm provides a new prospective for speckle suppression without the need for postprocessing. The multiplexing technology can double the capacity of current holographic systems and exhibits potential for various interesting display applications.
1 南开大学 现代光学研究所，天津 300350
2 光电传感器与传感网络天津市重点实验室，天津 300350
太赫兹(Terahertz，THz)波具有相干性好、信噪比高、辐射能量低等性质，在传感领域有着广泛应用。此外，THz传感还具有实时、非接触、无标记、非电离等优点，在生化传感特别是生物活性物质的传感中有着重要应用。但THz传感也存在着灵敏度低、水的吸收强、检测信息有限、适用性差等缺陷。介绍在THz时域偏振光谱传感技术方面的系列工作，采用微结构器件作为传感器，使用透射或反射传感方法分别检测了细胞、氨基酸和脱氧核糖核酸(DNA)几种生化样品。实验结果表明：与传统的谐振传感方法相比，偏振传感方法的品质因数和传感灵敏度均有着显著提高；反射式传感有效避免了水对THz的吸收，实现了液体环境下活性生化样品的传感；使用具有手性的微结构器件作为传感器，或利用手性THz波作为激发场，可以增强样品的偏振响应，提高传感灵敏度，实现手性分子的传感。
太赫兹传感 偏振 手性 微结构传感器 生化样品 terahertz sensing polarization chirality microstructure sensor biochemical samples 太赫兹科学与电子信息学报
2021, 19(6): 951
糖类是典型的手性物质，其在太赫兹波段的手性光谱尚未得到充分研究。本文研究了乳糖、半乳糖、葡萄糖3种糖类在低温和常温下的折射率和吸收谱，并通过太赫兹时域偏振光谱检测，获得了这些样品的手性光谱。实验结果显示，糖类吸收会随着温度降低而减弱，低温下有利于获得样品的手性特征；在80 K温度下，葡萄糖在1.3~1.5 THz频段表现出很强的圆二色性(CD)，在1.39 THz处CD谱峰值达到44.97%；在1.6~1.8 THz频段内，3种糖类都具有特定的手性特征峰，CD值均超过20%。研究结果对进一步认识手性生化样品在太赫兹波段的手性光谱及其内在机制具有重要参考价值。
太赫兹光谱 手性光谱 糖类 温度 terahertz spectroscopy chiral spectra saccharides temperature 太赫兹科学与电子信息学报
2021, 19(5): 819
1 中国科学技术大学纳米技术与纳米仿生学院, 安徽 合肥 230026
2 中国科学院苏州纳米技术与纳米仿生研究所, 江苏 苏州 215123
3 青岛翼晨镭硕科技有限公司, 山东 青岛 266000
4 中国科学院苏州纳米技术与纳米仿生研究所南昌研究院, 江西 南昌 330200
5 长春理工大学理学院高功率半导体激光国家重点实验室, 吉林 长春 130022
1.3 μm InAs/GaAs量子点(QD)激光器基于自身优异的光电特性,有望成为下一代光通信系统所急需的高性能、低成本光源。理论分析了提高量子点材料增益的几种方法,然后利用分子束外延(MBE)分别生长非掺杂、p型调制掺杂的8层高质量的量子点激光器外延结构,并分别制备了量子点激光器。另外,为了抑制量子点激发态与基态的激射竞争,设计并优化了激光器腔面的镀膜工艺。最终实现了300 μm超短腔长基态激射的p型调制掺杂1.3 μm InAs/GaAs的量子点激光器,展示出了其在高速光通信系统应用中的巨大潜力。
中国激光
2021, 48(16): 1601001
桂林电子科技大学 广西光电信息处理重点实验室, 广西 桂林541004
作为电压控制型器件, 压电陶瓷驱动电源的稳定性受负载电容量变化的影响严重。针对负载等效电容在驱动电压变化下的动态特性, 首次提出了一种基于容性负载的压电驱动电源。该电源采用RC前置滤波与电容超前反馈相结合, 提高了系统稳定性与驱动电源的鲁棒性。分析结果表明, 额定负载为1.5 μF的驱动电源优化后在0~3 μF内具有良好的动态性能, 且输出电压精度达0.7 mV。
压电驱动电源 动态容性负载 超前反馈 稳定性分析 压电控制 piezoelectric driving power dynamic capacitive load advanced feedback stability analysis piezoelectric control
Author Affiliations
Abstract
1 Key Laboratory of Nanodevice and Applications, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China
2 Vacuum Interconnected Nanotech Workstation, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China
3 Division of Natural and Applied Sciences, Duke Kunshan University, Kunshan 215316, China
4 School of Physics and Information Technology, Shaanxi Normal University, Xi’an 710119, China
5 Nano Science and Technology Institute, University of Science and Technology of China, Suzhou 215123, China
Graphene, as a saturable absorber (SA), has attracted much attention for its application in ultrashort pulse fiber lasers due to its ultrafast interband carrier relaxation and ultra-broadband wavelength operation. Nevertheless, during the stacking process of monolayer graphene layer, the induced nonuniform contact at the interface of graphene layers deteriorate the device performance. Herein, we report the fabrication of graphene saturable absorber mirrors (SAMs) via a one-step transfer process and the realization of the much enlarged modulation depth and the much reduced nonsaturable loss with tri-layer graphene (TLG) than single-layer graphene (SLG) due to the improved uniform contact at the interface. Moreover, the operation of 1550 nm mode-locked Er-doped fiber laser with the TLG SAM exhibits excellent output characteristics of the maximum output power of 9.9 mW, a slope efficiency of 2.4% and a pulse width of 714 fs. Our findings are expected to pave the way toward high-performance ultrashort pulse fiber lasers based on graphene SAs.
Journal of Semiconductors
2020, 41(1): 012302
