1 河北工业职业技术大学，石家庄16204，中国
2 Technical University of Denmark，Copenhagen 1599，Denmark
3 中国地质大学(北京)材料科学与工程学院，矿物材料国家专业实验室，非金属矿物与固废资源材料化利用北京市重点实验室，地质碳储与资源低碳利用教育部工程研究中心，北京100083，中国
密度泛函理论是一种基于量子力学原理的电子结构计算方法，已经成为材料科学和化学领域中重要的计算工具之一。在荧光材料研究中，密度泛函理论计算可以确定晶体结构，计算材料的的能带结构、态密度等信息来帮助研究人员理解荧光材料的本质和特性，为材料的设计和优化提供依据，同时基于密度泛函理论计算的高通量计算可以快速评估大量材料的性质，加快新材料的开发过程，降低研究成本。本文介绍了密度泛函理论计算在荧光材料研究中的应用，并探讨了其未来发展前景。
密度泛函理论 荧光材料 高通量计算 density functional theory fluorescent materials high throughput calculations
Author Affiliations
Abstract
1 Information and Navigation College, Air Force Engineering University, Xi’an 710077, China
2 College of Advanced Interdisciplinary Studies, National University of Defense Technology, Changsha 410073, China
3 College of Computer and Science, National University of Defense Technology, Changsha 410073, China
4 Teaching and Research Support Center, National University of Defense Technology, Changsha 410073, China
Remarkable progress has been made in satellite-based quantum key distribution (QKD), which can effectively provide QKD service even at the intercontinental scale and construct an ultralong-distance global quantum network. But there are still some places where terrestrial fiber and ground stations cannot be constructed, like harsh mountainous areas and air space above the sea. So the airborne platform is expected to replace the ground station and provide flexible and relay links for the large-scale integrated communication network. However, the photon transmission rate would be randomly reduced, owing to the randomly distributed boundary layer that surrounds the surface of the aircraft when the flight speed is larger than 0.3 Ma. Previous research of airborne QKD with boundary layer effects is mainly under the air-to-ground scenario in which the aircraft is a transmitter, while the satellite-to-aircraft scenario is rarely reported. In this article, we propose a performance evaluation scheme of satellite-to-aircraft QKD with boundary layer effects in which the aircraft is the receiver. With common experimental settings, the boundary layer would introduce a loss to the transmitted photons, decrease of the quantum communication time, and decrease of the secure key rate, which shows that the aero-optical effects caused by the boundary layer cannot be ignored. Our study can be performed in future airborne quantum communication designs.
satellite-to-aircraft quantum key distribution boundary layer aero-optical effects Chinese Optics Letters
2023, 21(4): 042702
1 西南科技大学 信息工程学院，四川 绵阳 621000
2 深圳市朗驰欣创科技股份有限公司，广东 深圳 518000
为解决低质量红外图像细节模糊、对比度低等问题，提出了并行多特征提取网络的红外图像增强方法，设计了结构特征映射网络和双尺度特征提取网络。结构特征映射网络用于建立全局结构特征权重，以保持原始图像的空间结构信息。双尺度特征提取网络采用多尺度卷积层和融合多空洞卷积的注意力，增强网络对上下文信息的关注力，提升网络对感兴趣区域的特征提取能力，同时学习不同尺度的特征信息，完成双尺度间信息的交换，生成目标增强映射，实现目标区域细节纹理自适应增强。实验证明，所提方法能有效提高对比度，避免过增强，丰富图像细节纹理，减少伪影和光晕现象，在BSD200数据集上的PSNR与SSIM较典型的传统方法和深度学习方法分别提升了约37.35%、2.1%与25.94%、3.15%，在真实红外数据集上分别提升了约30.62%、1.04%与24.83%、2.08%，且对不同对比度因子的低质量图像，文中方法也具有良好的增强效果。
红外图像 图像增强 深度学习 空洞卷积 注意力机制 infrared image image enhancement deep learning dilated convolution attention mechanism 红外与激光工程
2022, 51(8): 20210957
中国民航大学天津市民航能源环境与绿色发展工程研究中心，天津 300300
锂离子电池热失控气体引起的火灾爆炸事件层出不穷，通过分析相关热失控气体可以明确其发生发展机理，这有助于锂离子电池热失控早期预警技术的研究及安全性评估。采用高时间分辨率、高通量的激光拉曼光谱技术对热失控气体进行在线分析，确定了电池热解气体的主要成分为CO2、CO、H2、CH4、C2H4以及C3H6，并采用偏最小二乘法分别构建了包括空气成分(N2、O2)在内的特征气体的拉曼光谱定量模型，在线原位分析了锂离子热失控实际场景中特征气体的信息变化。结果表明，锂离子电池热失控气体拉曼光谱定量模型的相关系数大于0.91，均方根误差小于0.45%，高效实现了锂离子电池热失控过程中多组分烃类和非烃类气体的在线分析。
光谱学 拉曼光谱 锂离子电池 热失控 特征气体 在线分析 中国激光
2022, 49(23): 2311001
Author Affiliations
Abstract
1 School of Physics and Key Laboratory of Weak-Light Nonlinear Photonics, Nankai University, Tianjin 300071, China
2 National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
In free-space or in optical fibers, orbital angular momentum (OAM) multiplexing for information transmission has been greatly developed. The light sources used were well coherent communication bands, and the fibers used were customized. Here, we use an 810 nm femtosecond laser to generate optical vortices carrying OAM and then feed them into two kinds of commercial step-index few-mode fibers to explore the transmission characteristics of OAM modes. We also propose a method without multiple-input multiple-output digital signal processing to identify the input OAMs. It is of great guiding significance for high-dimensional quantum information experiments via the OAMs as a degree of freedom, using the light generated by the spontaneous parametric down-conversion as the source and the commercial fibers for information transmission.
060.2310 Fiber optics 050.4865 Optical vortices 080.4865 Optical vortices Chinese Optics Letters
2019, 17(12): 120601
