针对空间物体姿态快速测量问题，以构建视觉最小系统需求为依据，研究了一种基于二维主动位姿引导的单目视觉空间姿态测量方法，建立了单目相机、二维载台与倾角仪之间的姿态测量模型，实现了空间物体的姿态角的测量。该方法以大地倾角仪坐标系统一测量系统的测量基准，由精密二维载台引导单目相机覆盖地空大视野三维空间，通过前期标定设计完成了单目相机与二维载台之间的工装校准；建立了载台坐标系、摄像机坐标系以及大地倾角仪坐标系之间的姿态测量传递模型，实现了定轴旋转双视角拍照下的空间物体的姿态解算和角度测量。构建了实验验证环境，测角实验结果表明：在系统测量基准坐标系下，其俯仰角的测量误差≤0.82°,测量相对误差≤6.1%；其横滚角的测量误差≤0.43°，测量相对误差≤3.4%。

Mode-locked microcombs with flat spectral profiles provide the high signal-to-noise ratio and are in high demand for wavelength division multiplexing (WDM)-based applications, particularly in future high-capacity communication and parallel optical computing. Here, we present two solutions to generate local relatively flat spectral profiles. One microcavity with ultra-flat integrated dispersion is pumped to generate one relatively flat single soliton source spanning over 150 nm. Besides, one extraordinary soliton crystal with single vacancy demonstrates the local relatively flat microcomb lines when the inner soliton spacings are slightly irregular. Our work paves a new way for soliton-based applications owing to the relatively flat spectral characteristics.

大尺寸晶体材料是半导体、激光、通讯等领域的基础原料, 大尺寸、高品质晶体材料的制备已成为制约相关行业发展的瓶颈。我国面临的“卡脖子”技术中大多与关键基础材料相关。大尺寸晶体材料制备理论与技术是我国新材料产业高质量发展的一个重要方面, 也是提升相应高技术产业的基础, 突破大尺寸晶体材料的制备理论和技术是获得高品质大尺寸晶体材料的关键。探究并准确理解大尺寸晶体生长机理需要借助原位表征技术和多尺度计算模拟方法。单一的原位表征和模拟技术只能探究特定时间和空间范围内的结晶信息, 为了准确反映结晶过程需要综合应用多种方法。本文综述了最新的多尺度晶体生长研究的原位表征方法、多尺度计算模拟技术以及机器学习方法, 为发展结晶理论和控制晶体品质提供重要的实验和理论依据, 并将为提升大尺寸晶体生长工艺的开发而服务。

Straight plasma channels are widely used to guide relativistic intense laser pulses over several Rayleigh lengths for laser wakefield acceleration. Recently, a curved plasma channel with gradually varied curvature was suggested to guide a fresh intense laser pulse and merge it into a straight channel for staged wakefield acceleration [Phys. Rev. Lett. 120, 154801 (2018)]. In this work, we report the generation of such a curved plasma channel from a discharged capillary. Both longitudinal and transverse density distributions of the plasma inside the channel were diagnosed by analyzing the discharging spectroscopy. Effects of the gas-filling mode, back pressure and discharging voltage on the plasma density distribution inside the specially designed capillary are studied. Experiments show that a longitudinally uniform and transversely parabolic plasma channel with a maximum channel depth of 47.5 μm and length of 3 cm can be produced, which is temporally stable enough for laser guiding. Using such a plasma channel, a laser pulse with duration of 30 fs has been successfully guided along the channel with the propagation direction bent by 10.4°.

在实际应用中，有效的操控极化激元给纳米光子器件、亚波长成像、异常折射等领域带来了巨大的发展前景而广受关注，但传统介质材料中的极化激元的调控灵活度相对较低，不能满足现实的广阔需要成为具有挑战性的难题。然而，声子极化激元作为一种光子——声子强耦合的新型准粒子，与其他的极化激元相比，具有更强的束缚光的能力、更长的寿命以及更低的损耗，在亚波长尺度红外光调控领域能够发挥举足轻重的作用。近年来，随着对二维范德瓦尔斯晶体的相关研究及报道，能够承载双曲声子极化激元的介质材料步入大众视野，并且在具有超高分辨率的纳米成像技术的支持下，很多新颖的近场红外光学现象在多种操控手段下被发掘，这极大的丰富了人们对于极化激元的认知。此综述首先从双曲声子极化激元的机理入手，介绍了声子极化激元的概念、色散关系和近期被广泛关注的双曲介质（h-BN、α-MoO₃）。随后，总结了双曲声子极化激元在上述介质中的不同传播特性以及多种维度调控下的近场成像分析，例如改变范德华晶体的周围介质环境、谐振腔、金属天线的面内调控等等。最后，我们对声子极化激元的研究进行了展望。多样的调控手段展现了声子极化激元的丰富应用，这对纳米成像、集成光路、纳米透镜等红外纳米光子器件提供可借鉴的途径，同时在未来可能还会衍生出更多新兴领域。