为了实现窄带完美吸收，本文提出了一种简单的三层金-二氧化硅-金薄膜(MDM)结构。通过电磁波时域差分算法(FDTD)进行模拟仿真和理论计算，详细分析了该结构的可调谐吸收特性，同时建立了理论模型，分析了其中存在的电磁模式以及窄带完美吸收的物理机制。首先，利用电磁波时域差分算法和传输矩阵算法(TMM)对该结构进行了理论计算，详细地分析了各个结构参数对吸收光谱的影响。然后，对该结构形成的窄带完美吸收物理机制进行了分析讨论。最后，利用磁控溅射制备手段，成功制备了三层结构的样片。实验观测到的结果与理论仿真一致。实验结果表明：本文提出的窄带完美吸收结构，最窄带宽约为21 nm，最高吸收可达99.51%，基本实现了窄带完美吸收。本文研究成果为相关应用奠定了基础。

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.

近年来，金属卤化物钙钛矿发光材料由于具有优异的光电性能，被广泛地应用于金属卤化物钙钛矿发光二极管（Perovskite light-emitting diodes, PeLEDs），被视作下一代显示和照明领域的发光光源。激子利用率是影响PeLEDs效率的关键因素之一，研究者采用各种各样的方法将激子限制在钙钛矿发光层中，对激子能量回收利用以提高激子的利用率。文中将概述通过添加剂辅助法、器件界面工程和结构优化法，将传统荧光材料、磷光材料、热激活延迟荧光材料引入器件，改善绿光和蓝光PeLEDs的光电性能方面所做的尝试。并简要地介绍激子限制作用的原理，以及不同类型的发光材料引入PeLEDs中激子的能量转移机理和器件光电性能提升的物理机理。

Multilayer dielectric gratings (MLDGs) are crucial for pulse compression in picosecond–petawatt laser systems. Bulged nodular defects, embedded in coating stacks during multilayer deposition, influence the lithographic process and performance of the final MLDG products. In this study, the integration of nanosecond laser conditioning (NLC) into different manufacturing stages of MLDGs was proposed for the first time on multilayer dielectric films (MLDFs) and final grating products to improve laser-induced damage performance. The results suggest that the remaining nodular ejection pits introduced by the two protocols exhibit a high nanosecond laser damage resistance, which remains stable when the irradiated laser fluence is more than twice the nanosecond-laser-induced damage threshold (nanosecond-LIDT) of the unconditioned MLDGs. Furthermore, the picosecond-LIDT of the nodular ejection pit conditioned on the MLDFs was approximately 40% higher than that of the nodular defects, and the loss of the grating structure surrounding the nodular defects was avoided. Therefore, NLC is an effective strategy for improving the laser damage resistance of MLDGs.

全无机镉基金属卤化物CsCdCl₃因其独特的三维晶体结构而具有优异的稳定性、宽带自陷激子（Self⁃trapped excitons，STEs）发射和丰富的离子掺杂格位，在固态照明领域引起了广泛关注。然而，基于八面体畸变的STEs辐射复合的发光效率较低。本文采用简单的室温溶液法制备了一系列Mn²⁺离子掺杂的六方相CsCdCl₃∶x%Mn微米晶。在254 nm紫外光激发下，Mn²⁺掺杂的样品发出明亮的橙黄光，发射峰位于598 nm处，半峰宽为75 nm，荧光量子产率最高达99.1%。稳态和瞬态荧光光谱测试结果表明，Mn²⁺掺杂CsCdCl₃微米晶的宽光谱发射源自基质的STEs和Mn²⁺离子的d⁃d跃迁。同时，该材料还具备优异的空气、热、水稳定性。我们进一步将CsCdCl₃∶5%Mn²⁺荧光粉、商用荧光粉、深紫外或蓝光LED芯片封装成两种白光发光二极管器件，色度坐标分别为（0.36，0.35）和（0.40，0.36），显色指数分别高达91和83，有望成为新一代发光材料用于照明领域。

We review the recent biomedical detection developments of scanning near-field optical microscopy (SNOM), focusing on scattering-type SNOM, atomic force microscope-based infrared spectroscopy, peak force infrared microscopy, and photo-induced force microscopy, which have the advantages of label-free, noninvasive, and specific spectral recognition. Considering the high water content of biological samples and the strong absorption of water by infrared waves, we divide the relevant research on these techniques into two categories: one based on a nonliquid environment and the other based on a liquid environment. In the nonliquid environment, the chemical composition and structural information of biomedical samples can be obtained with nanometer resolution. In the liquid environment, these techniques can be used to monitor the dynamic chemical reaction process and track the process of chemical composition and structural change of single molecules, which is conducive to exploring the development mechanism of physiological processes. We elaborate their experimental challenges, technical means, and actual cases for three microbiomedical samples (including biomacromolecules, cells, and tissues). We also discuss the prospects and challenges for their development. Our work lays a foundation for the rational design and efficient use of near-field optical microscopy to explore the characteristics of microscopic biology.

随着科学技术的不断进步，**目标也向着小型化、超高速、低可探测度的趋势发展，因而对目标的探测与识别能力也提出了更高的要求。文中在深入分析点目标成像过程及其能量分布的基础上，提出基于偏态瑞利分布点目标能量计算方法，并通过红外辐射特性测量精度对比实验进行验证，得出应用该方法的辐射强度测量偏差可控制在8%以下，而且测量离散程度更小，可有效区分弥散点目标和背景灰度值，证明该方法具有良好的工程适用性，较高的测量精度且广泛的应用前景。