Hybrid metal-dielectric structures combine the advantages of both metal and dielectric materials, enabling high-confined but low-loss magnetic and electric resonances through deliberate arrangements. However, their potential for enhancing magnetic emission has yet to be fully explored. Here, we study the magnetic and electric Purcell enhancement supported by a hybrid structure composed of a dielectric nanoring and a silver nanorod. This structure enables low Ohmic loss and highly-confined field under the mode hybridization of magnetic resonances on a nanoring and electric resonances on a nanorod in the optical communication band. Thus, the 60-fold magnetic Purcell enhancement and 45-fold electric Purcell enhancement can be achieved. Over 90% of the radiation can be transmitted to the far field. For the sufficiently large Purcell enhancement, the position of emitter has a tolerance of several tens of nanometers, which brings convenience to experimental fabrications. Moreover, an array formed by this hybrid nanostructure can further enhance the magnetic Purcell factors. The system provides a feasible option to selectively excite magnetic and electric emission in integrated photonic circuits. It may also facilitate brighter magnetic emission sources and light-emitting metasurfaces with a more straightforward design.

通过水热法配合高温煅烧合成了斜方晶系Y₇O₆F₉∶Er，Yb晶体，该晶体可实现高效上转换发光且具有良好的高分子亲和性。利用高压静电纺丝技术将Y₇O₆F₉∶Er，Yb晶体颗粒与高分子化合物聚丙烯腈（PAN）复合，制备出了兼备温度传感特性、柔韧性和灵活性的Y₇O₆F₉∶Er，Yb/PAN纤维。977 nm激光激发下，晶体颗粒和复合纤维在303~433 K温度范围内均展示出高效的上转换发光和良好的温度传感特性，且复合纤维在测温范围内表现出优于晶体颗粒的温度灵敏度和分辨率。在303 K温度下有最大绝对灵敏度值1.143%·K^-1，在433 K温度下有最小的分辨率0.15 K。因此，具有柔韧性的复合纤维既有良好温度传感特性又可任意调节形态，适应复杂多样的应用环境，是可应用于实现智能穿戴领域温度传感性能的有效候选材料。

Synchronized rotation of unit cells in a periodic structure provides a novel design perspective for manipulation of band topology. We then design a two-dimensional version of higher-order topological insulator (HOTI) by such rotation in a triangular photonic lattice with C3 symmetry. This HOTI supports the hallmark zero-dimensional corner states and, simultaneously, the one-dimensional edge states. We also find that our photonic corner states carry chiral orbital angular momenta locked by valleys, whose wave functions are featured by the phase vortex (singularity) positioned at the maximal Wyckoff points. Moreover, when excited by a fired source with various frequencies, the valley topological states of both one-dimensional edges and zero-dimensional corners emerge simultaneously. Extendable to higher or synthetic dimensions, our paper provides access to a chiral vortex platform for HOTI realizations in the terahertz photonic system.

Singularities in the spectra of open systems, known as exceptional points (EPs), have been shown to exhibit nontrivial topological properties and enhanced sensitivities. Here, we propose a novel approach to realize the EPs in a plasmon-exciton hybrid system and explore their applications in enhanced nanoscale sensing technology. We consider a plasmon-exciton system composed of a gold nanorod and a monolayer WSe2. By controlling the geometric parameters of the nano-hybrid system, we obtain simultaneous coalescence of the resonance frequencies and loss rates of the hybrid system, which is a unique feature of EPs. Numerical simulations show its application in enhanced nanoscale sensing for environmental refractive indices. Our work opens the way to a new class of sensors based on EP-enhanced sensing, with intrinsic nanoscale sensitivity due to the sub-diffraction-limit size of the plasmon-exciton nano-hybrid system.

羟基磷灰石(HAP)具有优异的生物相容性、生物活性和缓慢的降解速率等特性, 有可能弥补透明质酸(HA)用作软组织填充材料的不足。本研究采用一步反应法制备均匀负载HAP颗粒的HA-HAP复合水凝胶, 分析了制备工艺参数对复合水凝胶理化性能的影响及调控方法, 评价了其细胞相容性。结果表明, 采用该方法制备的复合水凝胶含1.5%~3.0%HA、2.38%~15.8% HAP, 具有良好的灭菌稳定性。通过改变HAP含量和交联剂的用量可以调控复合水凝胶的力学性能、溶胀行为等理化性能。利用一阶指数衰减方程可以较好地拟合复合水凝胶的溶胀行为, 质量溶胀率在1 h时已达到平衡溶胀率的90%以上。复合水凝胶具有良好的HA酶降解性, 1500 U/mL的酶作用2 min后HA降解率超过95%, 复合水凝胶可以快速溃散; 加入HAP颗粒不仅使复合水凝胶有更好的可塑性, 而且更有利于面部软组织填充和轮廓修正。优化制备的可注射HA-HAP复合水凝胶具有可调的理化性能和良好的细胞相容性, 可以较长时间地保留在体内, 兼具促进组织修复或重建的潜力, 有望成为优良的软组织填充材料。

为研究热处理过程与异质结构筑对WO₃的光电化学效应的影响机制, 采用低温溶剂热法制备纳米花状WO₃, 通过热处理精确调控WO₃纳米花的活性晶面、晶粒尺寸及结晶度。进一步借助循环化学浴法, 构筑WO₃/CdS/α-S异质结, 并研究其光电化学性能与浓度效应。结果表明, (200)晶面是WO₃纳米花的主要暴露晶面, 且比例随热处理温度升高而增大。350 ℃热处理的WO₃纳米花表现出最高的光响应电流。通过构筑WO₃/CdS/α-S梯形异质结, 增强材料在可见光区的吸收, 以牺牲少部分载流子的方式提高整体光生载流子的分离效率, 促进WO₃的宏观光电化学效应的提升。