聚合物凝胶光子晶体及其对物理环境的响应

文中简要介绍了物理响应性光子晶体的国内外研究动态。重点介绍以下几种物理响应性光子晶体:温度响应性光子晶体,溶剂响应性光子晶体,电场响应性光子晶体,磁场响应性光子晶体,机械力响应性光子晶体等。     

光子晶体及其制备方法研究进展

光子晶体是具有光子能带及能隙的一类新型材料，具有奇特的性质和广阔的应用前景。本文简述了光子晶体的主要特征，重点阐述了三维有序结构光子晶体的制作方法，并介绍了调节光子带隙的手段。     

Structural Color Materials for Optical Anticounterfeiting

The counterfeiting of goods is growing worldwide, affecting practically any marketable item ranging from consumer goods to human health. Anticounterfeiting is essential for authentication, currency, and security. Anticounterfeiting tags based on structural color materials have enjoyed worldwide and long‐term commercial success due to their inexpensive production and exceptional ease of percept. However, conventional anticounterfeiting tags of holographic gratings can be readily copied or imitated. Much progress has been made recently to overcome this limitation by employing sufficient complexity and stimuli‐responsive ability into the structural color materials. Moreover, traditional processing methods of structural color tags are mainly based on photolithography and nanoimprinting, while new processing methods such as the inkless printing and additive manufacturing have been developed, enabling massive scale up fabrication of novel structural color security engineering. This review presents recent breakthroughs in structural color materials, and their applications in optical encryption and anticounterfeiting are discussed in detail. Special attention is given to the unique structures for optical anticounterfeiting techniques and their optical aspects for encryption. Finally, emerging research directions and current challenges in optical encryption technologies using structural color materials is presented.     

The control of spontaneous emission from a three-level atom in an anisotropic photonic crystal with two asymmetric bands

We theoretically investigate the spontaneous emission light of an excited three-level atom embedded in an anisotropic photonic crystal with two asymmetric bands. The property of spontaneous emission relating to the atomic position in a unit cell of the crystal is described with a position-dependent phase difference. The atomic transition in free space can be manipulated by the other associated transition coupling to photonic crystal. The result shows that the spontaneous emission spectra are effectively shifted and tuned by the atomic position-dependent phase, which results in the asymmetric distribution of the photonic density of states between two bands, and the increasing band can push the emitted light towards the other band. The physical process can be further illuminated through analyzing the emitted field in photonic crystal. The result perhaps offers an interesting route towards tunable photonic devices.     

三维光子晶体的制备技术研究进展

光子晶体是周期性介电结构．它能象周期性原子结构中的电子禁带一样．产生光子禁带。自从1987年Yablonovitch提出光子晶体的概念以来，有关光子晶体的各种研究非常活跃。本文回顾了三维光子晶体的制备技术研究现状，旨在激发不同学科领域研究人员的想象力和创造力．使他们从一些可能的光子晶体制造途径中有所裨益．并将这种可能性转变为现实。     

光子晶体--一种新型人工带隙材料

光子晶体是近十年来才发展起来的存在光子禁带的一种新型人工材料,具有操控光子行为的独特能力,在众多领域有着广泛的用途.介绍了光子晶体的结构特征,分析了光子带隙产生的物理机理,着重介绍了光子晶体材料中存在的新现象及其应用.     

Photonic Microcapsules Containing Single‐Crystal Colloidal Arrays with Optical Anisotropy

Colloidal particles with a repulsive interparticle potential spontaneously form crystalline lattices, which are used as a motif for photonic materials. It is difficult to predict the crystal arrangement in spherical volume as lattices are incompatible with a spherical surface. Here, the optimum arrangement of charged colloids is experimentally investigated by encapsulating them in double‐emulsion drops. Under conditions of strong interparticle repulsion, the colloidal crystal rapidly grows from the surface toward the center of the microcapsule, forming an onion‐like arrangement. By contrast, for weak repulsion, crystallites slowly grow and fuse through rearrangement to form a single‐crystal phase. Single‐crystal structure is energetically favorable even for strong repulsion. Nevertheless, a high energy barrier to colloidal rearrangement kinetically arrests the onion‐like structure formed by heterogeneous nucleation. Unlike the isotropic onion‐shaped product, the anisotropic single‐crystal‐containing microcapsules selectively display—at certain orientations but not others—one of the distinct colors from the various crystal planes.     

一维光子晶体的带隙特性研究

一维光子晶体是指介质只在一个方向成周期性排列的材料。利用薄膜光学的特征矩阵法研究了一维光子晶体的禁带特性,分析了填充率变化、厚度的随机扰动对光子带隙的影响。结果表明,随着填充率的变化,各能级的带隙率变化,并且存在一个极大值;厚度的随机扰动对光子带隙也有一定的影响,随机度不同,对光子带隙的影响也不一样。本研究对一维光子晶体的设计与制备有一定的参考价值。     

硅槽内自组装二氧化硅光子晶体

采用溶剂蒸发法在硅片上微槽内对不同粒径的SiO2微球进行组装,尝试利用刻有微槽的硅片与平坦衬底间形成的毛细管池限制胶体晶体的生长厚度,获得了具有显著光子带隙特征的光子晶体线形阵列,并在此基础上比较了不同实验条件如微球直径、毛细管池物理限制作用等对微球排列方式及规整度的影响.     

PMMA光子晶体及PMMA/TiO2光子晶体的制备及表征

用无皂乳液聚合法,制备单分散的聚甲基丙烯酸甲酯（PMMA）微球,并使其在重力和表面张力作用下自组装成PMMA光子晶体。用SEM研究其表面形貌,并对其进行光学性质的研究。此外还制备了PMMA／TiO2光子晶体,用AFM表征了其形貌,XRD表征了混合体系的TiO2的晶型。经光学性质研究表明,TiO2纳米粒子提高了光子晶体的折射率比,光子带隙红移。     

光子晶体的能带结构、潜在应用和制备方法

光子晶体是指具有光子能带和能隙的一类新型材料,它具有奇特的调节光子传播状态的特性．本文将从光子晶体的能带结构、潜在应用和制备方法三方面对其进行综述性介绍．由于光子晶体有着非常广阔的应用前景,这一领域已成为当今世界范围内的研究热点．     

光子带隙调制下发光体间的能量传递过程

光子晶体具有光子带隙和光子局域等特有性质,光物理过程在光子带隙调制下产生新的现象特点为制备新型光电材料提供了可能。通过对光子带隙调制作用的机理探讨,设计制备蛋白石及反蛋白石结构光子晶体。对其中发光体的荧光光谱和给体荧光寿命的实验研究表明,当光子带隙频段与能量传递过程中给体的发射光谱相重叠,能量传递过程将得到增强。     

胶体阵列及三维光子晶体制备的研究进展

单分散的胶体颗粒能自发排列成胶体阵列,其长程有序结构能获得许多特殊的性质.胶体阵列被用作制备可见光及近红外波长范围的光子晶体的基础.以其为模板制备的反蛋白石结构可拥有全光子禁带,为新一代光子器件开发和应用带来了希望.介绍了单分散胶体颗粒的主流制备方法,归纳总结了胶体阵列制备的几种方法和国内外最新的相关报道,简述了其在制备三维光子晶体领域的最新进展以及该领域国内外的研究进展.     

Staining diatoms with rhodamine dyes: control of emission colour in photonic biocomposites

The incorporation of rhodamine dyes in the cell wall of diatoms Coscinodiscus granii and Coscinodiscus wailesii for the production of luminescent hybrid nanostructures is investigated. By systematic variation of the substitution pattern of the rhodamine core, we found that carbonic acids are considerably better suited than esters because of their physiological compatibility. The amino substitution pattern that controls the optical properties of the chromophore has no critical influence on dye uptake and incorporation, thus a variety of biocomposites with different emission maxima can be prepared. Applications in biomineralization studies as well as in materials science are envisioned.     

反重力电诱导自组装构造二维亚微米有序结构

介绍了一种亚微米级聚苯乙烯微球悬浮液在外加电场下克服重力作用组装构造二维有序晶体结构的方法,研究了在自组装过程中电压 电流的变化关系,以及该方法组装得到的二维结构的紫外 可见光谱和微观结构。试验结果显示这是一种具有潜力的高效率制备大面积二维有序晶体结构的方法。     

光子晶体调制下的光电材料

光子带隙的存在不仅产生出一大批新型材料和器件,也能够提供一种特殊的物理环境-具有波长尺度的介电周期场.这种物理环境为各种光电材料中光物理过程和光电性质的调制提供一种新的可能性.本文综合分析了光子晶体调制下光功能材料的自发辐射、能量传递、太阳能电池的光电转换效率、光催化等几个方面研究现状及其应用.