宽禁带γ-CuI是一种具有优异光电和热电性能的p型透明半导体材料, 近年来受到广泛关注。但作为一种新兴材料, 其发光性能受材料缺陷影响的物理机理尚不清楚。本工作通过气相反应法制备了Cl掺杂的CuI薄膜, 采用电镜表征方法研究Cl掺杂对多晶CuI薄膜表面形貌和阴极荧光发光特性的影响, 并结合第一性原理计算探究了Cl在CuI薄膜中的主要存在形式, 以揭示Cl掺杂CuI薄膜结构与发光性能的联系。研究结果表明, 原本晶粒饱满但晶界显著的CuI薄膜掺杂Cl后呈现出致密平整的表面, 表明Cl掺杂剂改变了CuI的表面结构。相比未掺杂区域, Cl掺杂区410 nm处的荧光信号明显得到双倍增强, 而在720 nm附近的缺陷峰则略有降低, 说明Cl掺杂极大改善了CuI薄膜的发光性能。通过第一性原理计算对该现象进行理论分析, 发现引入Cl元素有效抑制了CuI中碘空位等深能级缺陷的产生, 降低了激子发生非辐射跃迁的概率, 从而改善CuI的发光性能, 这与阴极荧光的结果一致。本研究获得的掺杂CuI薄膜带边发光峰的半峰宽仅为7 nm, 表现出极高的发光单色性。这些发现有助于对卤素掺杂获得的高性能CuI基材料的理解。

Chirality plays an important role in biological processes, and enantiomers often possess similar physical properties and different physiologic functions. In recent years, chiral detection of enantiomers become a popular topic. Plasmonic metasurfaces enhance weak inherent chiral effects of biomolecules, so they are used in chiral detection. Artificial intelligence algorithm makes a lot of contribution to many aspects of nanophotonics. Here, we propose a nanostructure design method based on reinforcement learning and devise chiral nanostructures to distinguish enantiomers. The algorithm finds out the metallic nanostructures with a sharp peak in circular dichroism spectra and emphasizes the frequency shifts caused by nearfield interaction of nanostructures and biomolecules. Our work inspires universal and efficient machine-learning methods for nanophotonic design.

室温下利用阴极荧光光谱技术对ZnSe晶体进行了350~850 nm的无损全光阴极荧光图谱检测，分析了晶体内部缺陷及夹杂情况，室温下测得ZnSe晶体在400~550 nm的阴极荧光光谱，阴极荧光光谱测得462 nm处的ZnSe本征发光峰。缺陷处测得462 nm的本征发光峰和453 nm的缺陷发光峰，结合能谱分析，ZnSe晶体表面缺陷处的Zn：Se比约为6：4。阴极荧光图谱中缺陷处发光峰主要来自Zn夹杂缺陷发光。

采用离子注入方法在氢化物气相外延法生长的AlN薄膜中注入了不同剂量的Dy³⁺和Eu³⁺，制备了Dy³⁺单掺、Dy³⁺和Eu³⁺共掺的AlN样品.对于Dy³⁺单掺杂AlN样品，X射线衍射和拉曼散射实验结果表明随着Dy注入剂量的增加，样品的压应力也增加，形成了比较明显的损伤层；但当注入剂量由5×10¹⁴ at/cm²增加至1×10¹⁵ at/cm²时，压应力增加不明显，接近于饱和.对于Dy³⁺和Eu³⁺共掺的AlN样品，阴极荧光实验表明，AlN中Eu³⁺和Dy³⁺之间可能存在能量传递，能量传递途径为在声子辅助下从Dy³⁺的⁴F_9/2→⁶H_15/2至Eu³⁺的⁷F₀→⁵D₂的共振能量传递.此外，计算发现改变Dy³⁺和Eu³⁺离子的注入剂量比能实现发光色度坐标和色温的有效调控.

Cathodoluminescence (CL) as a radiative light produced by an electron beam exciting a luminescent material, has been widely used in imaging and spectroscopic detection of semiconductor, mineral and biological samples with an ultrahigh spatial resolution. Conventional CL spectroscopy shows an excellent performance in characterization of traditional material luminescence, such as spatial composition variations and fluorescent displays. With the development of nanotechnology, advances of modern microscopy enable CL technique to obtain deep valuable insight of the testing sample, and further extend its applications in the material science, especially for opto-electronic investigations at nanoscale. In this article, we review the study of CL microscopy applied in semiconductor nanostructures for the dislocation, carrier diffusion, band structure, doping level and exciton recombination. Then advantages of CL in revealing and manipulating surface plasmon resonances of metallic nanoantennas are discussed. Finally, the challenge of CL technology is summarized, and potential CL applications for the future opto-electronic study are proposed.