Strong light-matter interactions in two-dimensional transition metal dichalcogenides (TMDCs) with robust spin-valley degrees of freedom open up the prospect of valleytronic devices. A thorough understanding on the dynamics of the valley polarizations in the strong coupling regime is urgently required. Here, multiple polarized TMDCs-SPPs hybrid systems were constructed by combining monolayer WS2 flakes to linear, circular, and spiral Ag gratings, resulting in linear and circular polarized modulation on the coherent hybrid states, respectively. Particularly, valley polaritons can be tailored asymmetrically by chiral strong coupling regime. Furthermore, the dynamics of the polarized polaritons were directly analyzed by transient absorption (TA) measurement. Both of the linear and circular polarization difference in the TA spectra can be retained for a remarkable long time, leading to a polarized PL even at room temperature. More importantly, in the chiral strong coupled WS2-spiral Ag grating devices, the mechanism of the asymmetrical valley-polarized PL (p σ+ = 14.9% and p σ- = 10.8%) is proved by the opposite valley polarization dynamics in the circularly polarized TA spectra. The multiple polarization modulation in monolayer TMDCs-SPPs strong coupling devices could provide a viable route toward multiple polarization polaritonic devices.

射频前端的高度集成和高能量密度使声表面波(SAW)器件的非线性问题愈发严重。该文搭建了射频SAW器件非线性信号的测量系统，对SAW谐振器的二次谐波(H2)和三次谐波(H3)信号进行了准确测量。分析测量结果，讨论了非线性谐波信号的产生机制，并通过非线性有限元(FEM)模型仿真结果与测量结果拟合对比，验证了介电非线性和声应变的非线性效应对谐波产生的影响，为进一步研究非线性抑制方法，设计高线性度SAW器件提供了重要支撑。

针对铝镓氮光阴极像增强器极限分辨力远小于同结构类型砷化镓光阴极像增强器极限分辨力的问题，基于紫外光激发荧光粉发光的特性，搭建了铝镓氮光阴极的紫外光传输特性评测装置，对铝镓氮光阴极紫外光传输特性进行了测量，并依据非衍射光学系统传函方程推算了铝镓氮光阴极的紫外光学传递函数；依据近贴聚焦系统调制传递函数方程，并基于制备的铝镓氮光阴极像增强器的分辨力测试数据，推导了铝镓氮光阴极像增强器的前近贴聚焦系统调制传递函数方程；通过对比研究铝镓氮光阴极的紫外光调制传递函数方程和铝镓氮光阴极像增强管的前近贴聚焦系统调制传递函数方程对系统传函影响的比例权重，提出紫外光在铝镓氮光阴极内部传输时紫外光散射，以及紫外光激发载流子在铝镓氮激活层中的散射和发射电子散射均是造成铝镓氮光阴极像增强管极限分辨力低的因素，且紫外光激发载流子在铝镓氮激活层中的散射和发射电子散射是最主要的影响因素。

Manipulation of light-matter interaction is critical in modern physics, especially in the strong coupling regime, where the generated half-light, half-matter bosonic quasiparticles as polaritons are important for fundamental quantum science and applications of optoelectronics and nonlinear optics. Two-dimensional transition metal dichalcogenides (TMDs) are ideal platforms to investigate the strong coupling because of their huge exciton binding energy and large absorption coefficients. Further studies on strong exciton-plasmon coupling by combining TMDs with metallic nanostructures have generated broad interests in recent years. However, because of the huge plasmon radiative damping, the observation of strong coupling is significantly limited at room temperature. Here, we demonstrate that a large Rabi splitting (~300 meV) can be achieved at ambient conditions in the strong coupling regime by embedding Ag-WS₂ heterostructure in an optical microcavity. The generated quasiparticle with part-plasmon, part-exciton and part-light is analyzed with Hopfield coefficients that are calculated by using three-coupled oscillator model. The resulted plasmon-exciton polaritonic hybrid states can efficiently enlarge the obtained Rabi splitting, which paves the way for the practical applications of polaritonic devices based on ultrathin materials.

在反应温度为200 ℃、反应时间为8 h的温和条件下, 采用水热法合成了近红外到近红外的Mn2+掺杂NaYF4 ∶Yb3+/Tm3+上转换荧光纳米粒子, 再以两亲性聚合物C18PMH-mPEG作为亲水性配体修饰到上转换荧光纳米粒子表面, 得到具有水溶性的上转换荧光纳米粒子。然后在980 nm近红外光源激发下, 测量了上转换荧光纳米粒子的荧光发射光谱, 在(800±10) nm附近, 观察到了较强的单近红外光发射(3H4 →3H6)。对样品进行细胞毒性实验, 结果表明制得的水溶性Mn2+掺杂NaYF4 ∶Yb3+/Tm3+纳米粒子具有良好的生物相容性。并进一步在小鼠体内进行了近红外成像, 表明其在生物成像领域将会具有一定的应用前景。

针对晶体表面的损伤特性，采用小光斑扫描激光预处理技术预辐照DKDP晶体元件，并采用表面损伤自动探测系统实时分析每个脉冲辐照后晶体表面的损伤情况，比较预处理和未预处理区域的损伤点密度确定表面预处理效果，并进一步模拟分析表面各类缺陷在纳秒强激光辐照下的动态过程，解释激光预处理对精抛表面提升作用的微观机制并分析它对粗抛表面提升不明显的原因。实验结果表明，激光预处理技术对粗抛表面的提升作用并不明显，但是可以大幅度抑制精抛表面的损伤点密度。在本文的实验条件下，晶体表面的抗激光损伤能力可以提升约60%。比较体材料和精抛表面的预处理效果发现: 当体材料的抗破坏能力通过预处理提升后，精抛表面的抗激光损伤能力也会提升，由此可见精抛表面的激光预处理效果与体材料性能相关。

采用高温固相法制备了LiGd(WyMo1-y)2O8-x/2Fx∶0.4Eu3+ (x=0~1,y=0~1)系列白光LED用红色荧光粉。通过扫描电子显微镜、X射线衍射仪、红外光谱仪、荧光光谱仪对荧光粉的形貌、结构、光学性能进行了表征。结果表明, Eu3+、F-和WO2-4的掺杂没有改变LiGd(MoO4)2的四方晶系白钨矿结构; F-和WO2-4最佳掺杂量分别为x=0.6, y=0.4。在396 nm激发下, LiGd(W0.4Mo0.6)2O7.7F0.6∶0.4Eu3+的发光强度比未掺杂样品提高了60%, 量子效率可达66.23 %。当温度升高至100 ℃时, 样品的发射强度降为25 ℃时的76.6%。在460 nm激发下, 样品的最强窄带发射峰位于617 nm处, 归属于5D0→7F2跃迁, 色坐标为(0.649 9, 0.346 3)。5D0能级的荧光寿命曲线遵循单指数规律衰减, 随着F-掺杂浓度的增加, 5D0能级的荧光寿命不断增加, 归因于低声子能量的F-掺入有效减小了能量的无辐射跃迁概率。所制备的LiGd(W0.4Mo0.6)2O7.7F0.6∶0.4Eu3+荧光粉有望应用于白光LED。

传递辐射计是实现卫星遥感仪器在轨光谱辐射定标传递的核心设备, 也是地面实验室高精度光谱定标系统的关键。 介绍了不同机构研制的覆盖350～700, 700～2 500 nm谱段的多个传递辐射计的结构组成、 工作原理及辐射定标基准传递方式, 及其异同点的比对, 再通过它们在不同谱段的定标过程中所应用的关键技术的分析, 说明每种技术的优缺点和所能达到的精度, 及其应用条件。 文中通过对国际上标准计量机构采用的光谱辐亮度基准定标传递过程的介绍, 突出了传递辐射计系统的重要作用, 再结合其对光谱仪等遥感器定标光源的定标监测应用, 说明了传递辐射计在航天辐射定标领域的不可或缺性。 最后, 通过国内设计的新型传递辐射计的介绍, 对传递辐射计未来研究的发展方向和关键问题进行了展望, 并对传递辐射计搭配低温辐射计组成的未来实现可溯源国际单位制在轨基准定标传递系统所存在的研究难点予以预测分析。