钙钛矿材料具有优异的光学性能和较高的载流子迁移率，成为空间太阳能电池领域极具竞争力的材料。然而空间粒子辐照容易改变材料结构和光学性能，导致其性能下降。为了探究电子辐照对CsPbBr₃材料结构与光学特性的影响规律，本文开展了CsPbBr₃材料电子辐照实验，利用高分辨透射电子显微镜表征CsPbBr₃纳米晶微观形貌，并通过X射线衍射分析和X射线光电子能谱分析进一步探究晶体结构的变化趋势。研究发现：电子辐照后CsPbBr₃纳米晶形貌变得粗糙，尺寸明显减小，并且纳米晶在高剂量电子辐照下变得紧凑，形成纳米团簇。其次，通过稳态紫外-可见吸收光谱图与光致发光谱图表征CsPbBr₃材料的光学性能，并利用第一性原理计算分析辐照后晶格膨胀带来的带隙变化。研究证明电子辐照后纳米晶颜色加深，影响钙钛矿的透光率，进而增强了样品对光的吸收性能，同时电子辐照能够分解CsPbBr₃纳米晶，特别是高剂量辐照后其光致发光性能降低了53.7%～78.6%。本文研究结果为钙钛矿纳米晶空间辐射损伤机理及应用研究提供了数据支撑。

An optical micro/nanofiber (MNF) is a quasi-one-dimensional free-standing optical waveguide with a diameter close to or less than the vacuum wavelength of light. Combining the tiny geometry with high-refractive-index contrast between the core and the surrounding, the MNF exhibits favorable optical properties such as tight optical confinement, strong evanescent field, and large-diameter-dependent waveguide dispersion. Meanwhile, as a quasi-one-dimensional structure with extraordinarily high geometric and structural uniformity, the MNF also has low optical loss and high mechanical strength, making it favorable for manipulating light on the micro/nanoscale with high flexibility. Over the past two decades, optical MNFs, typically being operated in single mode, have been emerging as a miniaturized fiber-optic platform for both scientific research and technological applications. In this paper, we aim to provide a comprehensive overview of the representative advances in optical MNFs in recent years. Starting from the basic structures and fabrication techniques of the optical MNFs, we highlight linear and nonlinear optical and mechanical properties of the MNFs. Then, we introduce typical applications of optical MNFs from near-field optics, passive optical components, optical sensors, and optomechanics to fiber lasers and atom optics. Finally, we give a brief summary of the current status of MNF optics and technology, and provide an outlook into future challenges and opportunities.

Two-dimensional (2D) nonlinear optical mediums with high and tunable light modulation capability can significantly stimulate the development of ultrathin, compact, and integrated optoelectronics devices and photonic elements. 2D carbides and nitrides of transition metals (MXenes) are a new class of 2D materials with excellent intrinsic and strong light-matter interaction characteristics. However, the current understanding of their photo-physical properties and strategies for improving optical performance is insufficient. To address this issue, we rationally designed and in situ synthesized a 2D Nb₂C/MoS₂ heterostructure that outperforms pristine Nb₂C in both linear and nonlinear optical performance. Excellent agreement between experimental and theoretical results demonstrated that the Nb₂C/MoS₂ inherited the preponderance of Nb₂C and MoS₂ in absorption at different wavelengths, resulting in the broadband enhanced optical absorption characteristics. In addition to linear optical modulation, we also achieved stronger near infrared nonlinear optical modulation, with a nonlinear absorption coefficient of Nb₂C/MoS₂ being more than two times that of the pristine Nb₂C. These results were supported by the band alinement model which was determined by the X-ray photoelectron spectroscopy (XPS) experiment and first-principal theory calculation. The presented facile synthesis approach and robust light modulation strategy pave the way for broadband optoelectronic devices and optical modulators.

采用Chzochralski方法成功生长了Dy³⁺掺杂的SrGdGa₃O₇晶体, 并对其结构和光学特性进行了详细研究。基于XRD数据, 采用Rietveld法优化了晶体的晶格参数。分析了Dy: SrGdGa₃O₇晶体的偏振吸收谱、偏振发射谱和荧光衰减曲线。在452 nm处, π偏振和σ偏振对应的吸收截面分别为0.594×10^-21和0.555×10^-21 cm²。计算得到的有效J-O强度参数Ω₂、Ω₄和Ω₆分别为5.495×10^-20、1.476×10^-20和1.110×10^-20 cm²。J-O理论分析和荧光光谱表明: 在452 nm激发下, Dy: SrGdGa₃O₇晶体⁴F_9/2→⁶H_13/2跃迁在可见光波段具有最高的荧光分支比和荧光强度, 在574 nm处的π和σ偏振发射截面分别为1.84×10^-21和2.49×10^-21 cm²。Dy³⁺: ⁴F_9/2能级的辐射寿命和荧光寿命分别为0.768和0.531 ms, 量子效率为69.1%。研究结果表明: Dy³⁺: SrGdGa₃O₇晶体是一种潜在的可用于蓝光LD泵浦实现黄激光的材料。

氮掺杂金刚石（N-D）是最重要的碳基电子材料之一，由于氮相关色心的存在，其具有许多有趣而独特的物理特征。文章中研究了等离子体化学气相沉积法生长的N-D样品的太赫兹（THz）磁光特性。应用偏振THz时域光谱（THz TDS）技术，在0~8 T磁场和80 K温度条件下，测量了N-D样品在法拉第几何结构下的THz透射光谱，得到了N-D材料的法拉第旋转角和椭偏率、复横向（或霍尔）磁光电导率以及复左、右旋介电常数随磁场的变化规律。结果表明，N-D材料具有优良的THz磁光法拉第旋光效应，可应用于THz旋光器件。

Line-field Confocal Optical Coherence Tomography (LC-OCT) is an imaging modality based on a combination of time-domain optical coherence tomography and reflectance confocal microscopy. LC-OCT provides three-dimensional images of semi-transparent samples with a spatial resolution of ∼1 μm. The technique is primarily applied to in vivo skin imaging. The image contrast in LC-OCT arises from the backscattering of incident light by the sample microstructures, which is determined by the optical scattering properties of the sample, characterized by the scattering coefficient μ_s and the scattering anisotropy factor g. In biological tissues, the scattering properties are determined by the organization, structure and refractive indexes of the sample. The measurement of these properties using LC-OCT would therefore allow a quantitative characterization of tissues in vivo. We present a method for extracting the two scattering properties μ_s and g of tissue-mimicking phantoms from 3D LC-OCT images. The method provides the mean values of μ_s and g over a lateral field of view of 1.2 mm × 0.5 mm (x × y). It can be applied to monolayered and bilayered samples, where it allows extraction of μ_s and g of each layer. Our approach is based on a calibration using a phantom with known optical scattering properties and on the application of a theoretical model to the intensity depth profiles acquired by LC-OCT. It was experimentally tested against integrating spheres and collimated transmission measurements for a set of monolayered and bilayered scattering phantoms.