三角形硅烯纳米结构的等离激元激发

基于含时密度泛函理论,研究了等边三角形硅烯纳米结构的等离激元特性。沿三角形所在平面方向激发时,体系中有2个主要的等离激元共振带,其线形基本相同。这一特性与体系的边界构型以及尺度大小无关。沿垂直于纳米结构所在的平面方向激发时,体系中有2个等离激元共振带,分别位于6.8eV和15eV附近。这2个主要等离激元共振带的线形与三角形的大小以及边界的构型无关,其共振强度依赖于体系尺度的大小。     

表面等离激元滤波器的研究进展

表面等离激元滤波器是集成光学中一种非常重要的器件,能用来制造光开关,多路复用结构等多种设备。文章简要介绍表面等离激元滤波器的研究背景,总结报道了表面等离激元滤波器国内外的研究现状及其最新进展,指出表面等离激元滤波器在集成光学领域将会有非常重要的应用潜力。     

表面等离激元结构色研究进展

表面等离激元结构色是一种由可见光与金属微纳结构相互作用而产生的颜色。为了分析不同金属微纳结构对可见光特性的调控特性,本文选取了几种典型结构包括纳米光栅、亚波长孔阵列及多层堆叠结构,探究了其选频机理以及滤色效果。本文主要介绍了近几年来相关领域的最新发展成果,并对不同器件的应用范围,现存问题以及发展趋势做出了评述。表面等离激元结构色微纳器件优秀的滤波特性以及良好的电学响应,使其在超高分辨率显示和远程实时光调控等领域具备重大潜力。

     

金属纳米颗粒在表面等离激元共振生物传感器上的应用

文章研究不同形状和长径比的金属纳米颗粒应用在表面等离激元共振（SPR）生物传感器中对传感信号的影响,自制金属纳米颗粒并进行物理表征,以金纳米颗粒与抗兔IgG进行生物偶联,利用自制角度检测型SPR生物传感器对兔IgG抗体进行检测,结果表明,金属颗粒的形状和长径比对SPR传感器的共振角都有影响,金纳米棒能够明显提高SPR生物传感器的检测灵敏度。     

真空镀膜法制备纳米铝颗粒膜及其表面等离激元共振特性研究

采用直流磁控溅射镀膜技术制备了纳米铝颗粒膜,并尝试通过两种方式获得纳米铝的表面等离激元共振吸收峰,一种是先在室温石英基底上沉积纳米铝,再进行真空退火;另一种是在热石英基底上沉积纳米铝。用透射电镜和扫描电子显微镜、X-射线光电子谱、紫外-可见吸收光谱表征了样品的形貌和晶态结构、成份和吸收特性。采用比对的方式,研究了基底温度、沉积时间对两种方法制备的纳米铝表面等离激元共振的影响。结果表明,先沉积纳米铝,再进行真空退火,不能获得表面等离激元共振吸收峰,而在热基底上沉积纳米铝,可以获得明显的表面等离激元共振吸收峰。通过调控沉积时间和沉积温度实现了纳米铝表面等离激元共振峰从紫外光区到可见光区的可控移动。而且,研究发现对于平均厚度大于3 nm的纳米铝薄膜,由于纳米铝氧化具有自限性,其表面等离激元共振特性在空气中稳定且主要取决于纳米铝颗粒的团聚度。本研究对理解纳米铝表面等离激元共振特性及其应用具有指导意义。     

传感品质因数增强的塔姆-表面等离激元杂化模式

基于棱镜耦合的金膜表面塔姆等离激元(Tamm plasmon polarition, TPP)与表面等离极化激元(surface plasmon polariton, SPP)的杂化耦合受到广泛的关注和研究,但这种传统的激发装置由于拥有体积庞大的棱镜等光学元件以及对入射光角度精准控制有严格要求,限制了其集成化发展和实际应用。为了简化TPP和SPP杂化耦合激发方式,本文提出了一种光栅耦合型多层堆叠结构设计。该结构主要包括三部分：顶部纳米厚度的金膜、中间一维布拉格光子晶体以及底部金纳米光栅。在该结构中利用底部纳米光栅的一级透射光同时实现了顶部金膜上下表面SPP和TPP共振激发。两种模式之间的耦合杂化作用极大地减少了模式的共振带宽,从而使TPP-SPP模式的传感品质因数得到了显著的提高。此外,通过改变纳米光栅的周期和组成一维布拉格光子晶体的介质层厚度,SPP和TPP可以在较宽光谱范围内实现耦合杂化。相比于传统棱镜式的TPP和SPP双模式耦合结构,设计的光栅耦合型的多层堆叠结构无需借助棱镜和对入射角精确调控,在正入射光照射下就可实现两种模式的共振耦合,这不仅易于结构的进一步集成和小型化,同时对...     

空间填充型曲线的人工局域表面等离激元共振特性研究

本文提出了一种基于空间填充曲线的超构表面结构,利用理论分析、数值仿真的方法研究了该超构表面的近场电磁特性,实现了高度局域及高品质因子(Q-factor)的多阶人工局域表面等离激元共振(spoof plasmon resonances)。我们发现采用不同结构形状和尺寸的空间填充曲线均可产生共振频率规则分布的多阶谐振模式,通过调整结构的等效波导长度,可同时获得高的谐振波长/结构尺寸压缩比与高品质因子。空间填充曲线所支持的人工局域表面等离激元由磁偶极子与电偶极子模式交替支持;其余参数不变的情况下改变空间填充曲线的分布形式,结构所支持的表面等离激元的谐振特性不受形状曲折的影响,而只与等效波导总长度有关。此外,近场模式的强度分布随着空气波导的走向而改变,可根据实际需求对结构进行特定排布。本文的研究结果对设计基于空间填充曲线的小型化高品质因子电磁谐振器件具有重要的指导意义。     

表面等离激元应用研究新进展

表面等离激元(SPP)是一种特殊的电磁模式,由于其具有的特殊性质,SPP被广泛用于许多前沿技术领域。综述了SPP在提高薄膜太阳能电池的转化效率,增加光学透镜分辨率,增强生物传感器灵敏度方面的研究新进展。     

Ag纳米颗粒等离激元光散射增强对Si刻蚀形貌的影响机制

通过实验与有限元(FDTD)模拟系统研究了不同粒径尺寸的Ag纳米颗粒在P(100)Si表面刻蚀过程中等离激元光散射增强对刻蚀孔形貌的影响。SEM结果表明,刻蚀孔由与粒径尺寸接近的垂直孔演化为一种上大下小的火炬状形貌特征孔,该孔的直径与纳米颗粒尺寸散射半径相仿。模拟不同粒径的Ag纳米颗粒进入刻蚀孔后的光散射特征,证实了Ag纳米颗粒等离激元散射对刻蚀孔初期形成的重要作用。分析表明,基于光照条件下电子-空穴的激发特征,刻蚀孔的形貌主要依赖Ag纳米颗粒等离激元散射的光增强,即通过改变入射光频率以及Ag纳米颗粒粒径可以有效地调控Si表面形貌特征。Ag纳米颗粒等离激元光散射增强技术在Si基太阳能电池、发光二极管(LED)器件等领域有潜在应用前景。     

石墨烯及碳纳米管实空间等离激元学的最新进展

表面等离激元是金属和掺杂半导体中光子与电子的杂化激发模式。表面等离激元的强局域电场增强效应和强限域效应可以为在亚波长尺度操控光提供新的机遇。在这篇综述中,我们将首先讨论二维石墨烯等离激元在实空间中所展示出的各种新奇物理现象的最新进展。之后我们将总结在实空间观测到的一维金属以及半导体单壁碳纳米管中的Luttinger液体等离激元。石墨烯和碳纳米管为操控等离激元响应提供了非常有前景的研究平台,同时也为探索新奇量子现象和实现纳米光电器件提供了新的可能性。     

Plasmonic Metallic Heteromeric Nanostructures

Binary, ternary, and other high‐order plasmonic heteromers possess remarkable physical and chemical properties, enabling them to be used in numerous applications. The seed‐mediated approach is one of the most promising and versatile routes to produce plasmonic heteromers. Selective growth of one or multiple domains on desired sites of noble metal, semiconductor, or magnetic seeds would form desired heteromeric nanostructures with multiple functionalities and synergistic effects. In this work, the challenges for the synthetic approaches are discussed with respect to tuning the thermodynamics, as well as the kinetic properties (e.g., pH, temperature, injection rate, among others). Then, plasmonic heteromers with their structure advantages displaying unique activities compared to other hybrid nanostructures (e.g., core–shell, alloy) are highlighted. Some of the main most recent applications of plasmonic heteromers are also presented. Finally, perspectives for further exploitation of plasmonic heteromers are demonstrated. The goal of this work is to provide the current know‐how on the synthesis routes of plasmonic heteromers in a summarized manner, so as to achieve a better understanding of the resulting properties and to gain an improved control of their performances and extend their breadth of applications.     

Resistless Nanoimprinting in Metal for Plasmonic Nanostructures

Metal nanostructures are the main building blocks of metamaterials and plasmonics which show many extraordinary properties not existing in nature. A simple and widely applicable method that can directly pattern metals with silicon molds without the need of resists, using pressures of <4 MPa and temperatures of 25–150 °C is reported. Three‐dimensional structures with smooth and vertical sidewalls, down to sub‐10 nm resolution, are generated in silver and gold films in a single patterning step. Using this nanopatterning scheme, large‐scale vivid images through extraordinary optical transmission and strong surface‐enhanced Raman scattering substrates are realized. Resistless nanoimprinting in metal (RNIM) is a new class of metal patterning that allows plasmonic nanostructures to be fabricated quickly, repeatedly, and at a low‐cost.     

Morphology-Controlled Growth of AIN One-Dimensional Nanostructures

Aluminum nitride (AIN) nanowires, serrated nanoribbons, and nanoribbons were selectively obtained through a simple chloride assisted chemical vapor deposition process. The morphologies of the products could be controlled by adjusting the deposition position and the flux of the reactant gas. The morphologies and structures of the AIN products were investigated in detail. The formation mechanism of the as-prepared different morphologies of AIN one-dimensional (1D) nanostructures was discussed on the basis of the experimental results.     

Morphology-Controlled Growth of AlN One-Dimensional Nanostructures

Aluminum nitride （AIN） nanowires, serrated nanoribbons, and nanoribbons were selectively obtained through a simple chloride assisted chemical vapor deposition process. The morphologies of the products could be controlled by adjusting the deposition position and the flux of the reactant gas. The morphologies and structures of the AIN products were investigated in detail. The formation mechanism of the as-prepared different morphologies of AIN one-dimensional （ID） nanostructures was discussed on the basis of the experimental results.     

Hot Spot Engineering in Hierarchical Plasmonic Nanostructures

The controllable nanogap structures offer an effective way to obtain strong and tunable localized surface plasmon resonance (LSPR). A novel hierarchical plasmonic nanostructure (HPN) is created by incorporating a rotating coordinate system into colloidal lithography. In this nanostructure, the hot spot density is increased drastically by the long-range ordered morphology with discrete metal islands filled in the structural units. Based on the Volmer–Weber growth theory, the precise HPN growth model is established, which guides the hot spot engineering for improved LSPR tunability and strong field enhancement. The hot spot engineering strategy is examined by the application of HPNs as the surface-enhanced Raman spectroscopy (SERS) substrate. It is universally suitable for various SERS characterization excited at different wavelengths. Based on the HPN and hot spot engineering strategy, single-molecule level detection and long-range mapping can be realized simultaneously. In that sense, it offers a great platform and guides the future design for various LSPR applications like surface-enhanced spectra, biosensing, and photocatalysis.     

Circular Dichroism Studies on Plasmonic Nanostructures

In recent years, optical chirality of plasmonic nanostructures has aroused great interest because of innovative fundamental understanding as well as promising potential applications in optics, catalysis and sensing. Herein, state‐of‐the‐art studies on circular dichroism (CD) characteristics of plasmonic nanostructures are summarized. The hybrid of achiral plasmonic nanoparticles (NPs) and chiral molecules is explored to generate a new CD response at the plasmon resonance as well as the enhanced CD intensity of chiral molecules in the UV region, owing to the Coulomb static and dynamic dipole interactions between plasmonic NPs and chiral molecules. As for chiral assembly of plasmonic NPs, plasmon–plasmon interactions between the building blocks are found to induce generation of intense CD response at the plasmon resonance. Three‐dimensional periodical arrangement of plasmonic NPs into macroscale chiral metamaterials is further introduced from the perspective of negative refraction and photonic bandgap. A strong CD signal is also discerned in achiral planar plasmonic nanostructures under illumination of circular polarized plane wave at oblique incidence or input vortex beam at normal incidence. Finally perspectives, especially on future investigation of time‐resolved CD responses, are presented.     

Flexible One-Dimensional Nanostructures:A Review

This review discusses the recent reports on one-dimensional(1D) nanostructures with unusual flexibility.We discuss the importance that flexibility could have in future applications of nanowires and other nanostructures,and detail the two main approaches that have been followed to this day to synthesize highly flexible 1D nanostructures.One approach is based on making crystals in which one or two dimensions of the structure are comparable in size with the unit cell.Such thinness has been shown to provide unusual flexibility.The other approach conjoins hard nanostructures with flexible joints.     

准一维纳米结构ZnO的制备研究进展

准一维纳米结构ZnO因其优良的光电性质,在制作纳米电子器件和纳米光电子器件等许多领域表现出巨大的应用潜力.对准一维纳米结构ZnO在衬底上的制备生长方法、性质及衬底的影响作了简要的叙述.     

Self‐Aligned Anisotropic Plasmonic Nanostructures

Great opportunities emerge not only in the generation of anisotropic plasmonic nanostructures but also in controlling their orientation relative to incident light. Herein, a stepwise seeded growth method is reported for the synthesis of rod‐shaped plasmon nanostructures which are vertically self‐aligned with respect to the surface of colloidal substrates. Anisotropic growth of metal nanostructure is achieved by depositing metal seeds onto the surface of colloidal substrates and then selectively passivating the seed surface to induce symmetry breaking in the subsequent seed‐mediated growth process. The versatility of this method is demonstrated by producing nanoparticle dimers and linear trimers of Au, Au–Ag, Au–Pd, and Au–Cu₂O. Further, this unique method enables the automatic vertical alignment of the resulting plasmonic nanostructures to the surface of the colloidal substrate, thereby making it possible to design magnetic/plasmonic nanocomposites that allow the dynamic tuning of the plasmon excitation by controlling their orientation using an external magnetic field. The controlled anisotropic growth of colloidal plasmonic nanostructures and their dynamic modulation of plasmon excitation further allow them to be conveniently fixed in a thin polymer film with a well‐controlled orientation to display polarization‐dependent patterns that may find important applications in information encryption.     

准一维纳米材料制备方法的研究现状和发展趋势

本文介绍了准一维纳米结构所包含的一些基本概念以及在纳米科技中的重要地位.系统综述了近年来准一维纳米结构在制备方法方面的研究进展,并展望了其未来研究的发展方向.这对于目前准一维纳米结构的研究选题、方法借鉴都有重要的参考价值和指导意义.