光子晶体

光子晶体是20世纪80年代末提出的新概念和新材料,光子晶体中存在着光子能隙,正是由于这种光子能隙的出现,产生许多新的物理现象,这种新的物理现象具有重大的理论价值,简单介绍光子晶体的概念和特征,光子晶体的制备方法和理论研究方法,最后简单给出光子晶体的应用。     

光子晶体在光催化领域的研究进展

光子晶体是由具有不同介电常数的物质,在空间按照周期性排列形成具有光子带隙的介电结构材料.光子带隙中的慢光子和带隙反射可以促进光子的捕获和控制光与物质之间的相互作用.基于光子晶体独特的光学特性和较大的比表面积,将光子晶体结构引入到半导体光催化材料的设计中,可以有效地增强光催化反应活性.本文介绍了三维光子晶体的制备方法及慢光子效应,总结了光子晶体特别是反蛋白石结构的光子晶体作为光催化剂在废水净化、制氢、二氧化碳的转化等领域的研究进展,并针对光子晶体光催化剂面临的挑战,提出了开发具有不同折射率和周期性的多层三维光子晶体,促进光子晶体在光催化领域的应用.     

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呈周期性排列的材料。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，各能级的带隙率随填充率的变化而变化，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影响，但随机度不同，对光子带隙的影响也不一样。     

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.     

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。     

三维光子晶体研究进展

光子晶体是电子晶体的光学相似物,它是一种周期性的介电结构物,根据晶体的对称性,其介电常数在空间是变化的.三维光子晶体具有完全的光子带隙,在该结构中某一能量范围,光子不能在任一方向传播,这种光学特性在科学上有重要的应用价值.阐述了三维光子晶体结构具有潜在的光学特性,介绍了一些制备方法和存在的难题,以及对未来三维光子晶体的展望.     

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。     

非空气-石英结构PCF的带隙特性分析

光子晶体光纤是近十来年兴起的一个新兴的研究领域,是现今纤维光学的研究重点,光子带隙特性是光子晶体光纤区别传统光纤的主要特征。本文利用全矢量平面波展开法对非空气-石英结构PCF的带隙特性进行分析,并且重点讨论空气孔内填充介电材料对光子带隙存在的影响。     

浅析微波技术中光子晶体的具体运用

光子晶体作为一种介质材料,其介电常数呈光波长量级周期性分布,它具有光子带隙,并禁止频率在带隙中的电磁波传播。在微波频率范围的光子带隙被称为电磁带隙,其特有的性质使光子晶体在微带线和微波天线等方面得到了很广泛的应用,本文就其在微波技术领域的应用研究进行若干探讨。     

光子晶体传感器的研究进展

光子晶体是一类具有光子能带和带隙的新型光学材料,近年来已成为传感器技术领域的研究热点。光子晶体微腔、光子晶体波导、光子晶体光纤在传感器领域得到了广泛应用,而凝胶光子晶体、反蛋白石光子晶体、分子印迹光子晶体则实现了化学生物传感器的"裸眼检测技术"。重点分类介绍了一维、二维、三维光子晶体的制备及其在传感器领域的应用进展。     

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。     

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。     

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.