超分子材料的发展

本文综述了超分子材料的发展概况 ,并重点介绍了超分子器件、超分子液晶、仿超分子生物材料和超分子纳米材料等超分子化技术的研究进展 ,展望了超分子材料的发展前景及其开发应用潜力     

超材料吸波体研究进展与展望

采用吸波材料的隐身技术是最重要的隐身方式之一,它被广泛地应用在军用和民用等各个领域。综述了当前国内外吸波材料的最新研究进展,介绍了吸波原理及吸波材料的分类及其应用。重点论述了超材料吸波体的分类和研究现状。最后展望了超材料吸波体的努力方向和发展前景。     

新型聚合物多孔材料的制备研究进展

介绍了超浓乳液的形成及其特点,综述了超浓乳液作模板制备聚合物多孔材料的方法、机理和化学改性等方面的研究进展,并对其发展前景进行了展望.     

材料超塑性和超塑成形/扩散连接技术及应用

大量的工程材料都具有超塑性,以材料超塑性为理论基础的超塑成形/扩散连接技术是先进制造技术的一种,在航空航天等许多工业部门得到了越来越多的应用.分析了材料超塑性现象,超塑性变形机理研究进展,超塑成形/扩散连接技术的理论基础.以及超塑成形/扩散连接复合工艺的技术优势、研究进展和应用现状,并展望了超塑成形/扩散连接技术的发展趋势.     

超材料的应用及制备技术研究进展

超材料是一类具有特殊性质、自然界中并不存在的人造材料。综述了单负超材料和左手超材料构型的研究进展和超材料在超分辨成像、电磁隐身和电磁吸波体等方面的应用。同时也对国内外主要超材料制备技术进行了分类和概述,包括电子束光刻、纳米压印技术和聚焦离子束技术等。最后对超材料的发展方向和应用方向进行了展望。     

热学超材料研究进展

热学超材料是超材料家族的新成员,从一开始就备受瞩目,尤其近年来得到迅猛发展。本文以热学超材料关键技术为主线,着眼于坐标变换的基本理论和先进超材料的新奇性质,综述了近年来热学超材料的研究进展,重点关注其在热隐身、热防护、热管理和热信息等方面的应用前景。基于热学超材料的研究现状和发展趋势,进行了系统性的分类梳理,分析和归纳了近年来相关研究的内容与特色,给出了未来热学超材料在隐身、热管理、信息等领域的研究展望。

     

超浸润膜材料的制备方法及其在含油污水处理中的研究与应用状况

随着工业的不断发展,对含油污水进行处理以实现资源的回收和利用迫在眉睫。对含油污水而言,超浸润材料由于其高分离效率和低能耗而成为处理含油污水最有前景的材料之一。在各种处理方法中,膜分离法由于具有低能耗、绿色环保等优点成为未来最受欢迎的处理方法之一。介绍了膜表面浸润性的基本理论以及超浸润表面的制备方法,并进一步阐述了超浸润膜材料用于各类多油废水处理的研究状况,最后对其未来的发展趋势进行了展望。     

超疏水光热转换材料的研究进展

光热转换材料可以将可再生的太阳能高效转换为热能,并在海水淡化、废水净化等领域取得了良好效果,但受限于材料本身的性质缺陷,难以大规模应用。最近的研究表明,超疏水特性可防止污染物附着在材料表面的光热位点,研究者通过超疏水改性,赋予了光热转换材料以优异的自清洁性能。该创新策略极大地提高了光热转换材料的稳定性和持久性,为光热转换材料的实际推广应用提供了可能性。详细介绍了超疏水改性的方法、过程和机理,并重点综述了超疏水光热转换材料的最新研究进展和应用案例。最后,辩证分析了超疏水光热转换材料面临的挑战以及优化策略,进一步展望了超疏水光热转换材料的发展趋势和工程应用前景。     

无机粉末电致发光材料的研究进展

无机粉末电致发光材料包括硫化物系和金属氧化物系。主要从引入杂质缺陷和结构缺陷的角度阐述了国内外无机粉末电致发光材料在制备、性能及应用的最新研究进展情况，介绍了电致发光材料与超材料和纳米激光领域的结合进展。结合当前纳米材料科学的发展状况，展望了无机粉末电致发光材料的应用前景和发展趋势。     

基于超材料的红外/雷达兼容隐身材料研究进展

运用各种侦察探测手段，实现战场透明化是现代信息化战争的一个基本特点。红外探测和雷达探测被广泛应用于战场，这促使红外/雷达兼容隐身技术成为了对抗探测的研究重点。相较于传统红外/雷达兼容隐身材料，基于超材料的新型红外/雷达兼容隐身材料表现出更加优异的性能。本文对实现红外/雷达兼容隐身的原理和途径进行了阐述，重点综述了基于光子晶体、吸波超材料和编码超材料的红外/雷达兼容隐身材料的研究现状以及进展，并分析了红外/雷达兼容隐身材料的发展趋势。     

A Review of Metamaterial Invisibility Cloaks

The exciting features of metamaterial in conjunction with transformation optics leads to various applications in the microwave regime with such examples as invisible cloak, frequency selective surfaces (FSS), radomes, etc. The concept of electromagnetic invisibility is very much important in aerospace platform. Hence to study the feasibility of implementation of this concept for stealth, an extensive literature survey of metamaterial cloaks has been carried out and reported in this paper along with the basic concept of cloaking. To make the review more effective, the technical papers are classified into three broad sections viz. mathematical modeling, design and simulations, and fabrications and experimental demonstration. Further the design and simulation is focused on different techniques implemented such as finite difference time domain (FDTD), finite element method (FEM), finite integration technique (FIT), inductor-capacitor representation of metamaterial (LC MTM) etc. The review also reports the methods implemented for analysis of metamaterial cloaks with possibility of application to the specific frequency range.     

Arbitrary polygonal cloaks with multiple invisible regions

Arbitrary polygonal cloaks with multiple invisible regions are achieved by transformation optics. The original total space is divided into several layers. Choosing proper spatial mappings for these layers, a few empty layers in which objects can be hidden without bringing any scattering are available as extended invisible regions. Compared with the original polygonal cloaks the proposed one can provide multiple interior and/or exterior invisible regions simultaneously, and the objects can thus be hidden in the interior cavity and/or in the exterior space, or even be embedded into the gap between the cloaking shells.     

Three-dimensional elliptical cloak by impedance design of meta-composite cloak shell structure

Abstract

Research into metamaterials with unique material properties has led to the development of acoustic cloaks. The use of a spatially transformed space makes it possible to change (i.e. redirect) the propagating path of an acoustic wave using an anisotropic shell material as a cloak. However, the cloak of an acoustic wave in air, based on spatial transformation, requires an anisotropic cloak shell with unique properties, such as a mass density less than air that is not found in nature and is hard to be realized. We overcome the difficulties by providing a new concept in acoustic metamaterial design based on the impedance of the cloak shell. Using this method, we propose a new meta-composite material structure and further, design an elliptic meta-composite cloak shell complying with a three-dimensional space transformation. The new meta-composite material comprises a specially designed structure of layered plastic block elements forming cavities and pipes, respectively. Analysis of acoustic waves passing through the cloak shell demonstrates the effectiveness of acoustic cloaking performance over a frequency range of 800 to 1250 Hz in a 1/3 octave band. The anisotropic properties of the proposed cloak make it possible to alter the direction of the acoustic waves propagating from the original path and direct them to travel along a pre-determined path. This meta-composite material design accomplishes the goal of realizing an invisible elliptical acoustic cloak in the air.     

Emerging Trends in Terahertz Metamaterial Applications

The terahertz spectrum of electromagnetic waves is finding its position in various applications of day to day life because of its unique properties, including the penetration through opaque materials. Naturally occurring materials in this range are rare due to the display of a natural breakpoint of both electric, and magnetic resonances in these materials. However recent advances in artificially engineered materials, which show resonance in this region are able to harness desirable properties in the terahertz region. In this paper, terahertz design and fabrication issues have been explored along with their applications. A brief review of metamaterial terahertz applications has been carried out including metamaterial absorbers, filters, modulators, switches, lenses, and cloaking structures. The various patterns of metamaterial unit cells are discussed elaborately along with the possibility of flexible active terahertz structures.     

Invisibility and Cloaking Based on Scattering Cancellation

Advances in material synthesis and in metamaterial technology offer new venues to tailor the electromagnetic properties of devices, which may go beyond conventional limits in a variety of fields and applications. Invisibility and cloaking are perhaps one of the most thought‐provoking possibilities offered by these new classes of advanced materials. Here, recently proposed solutions for invisibility and cloaking using metamaterials, metasurfaces, graphene and/or plasmonic materials in different spectral ranges are reviewed and highlighted. The focus is primarily on scattering‐cancellation approaches, describing material challenges, venues and opportunities for the plasmonic and the mantle cloaking techniques, applied to various frequency windows and devices. Analogies, potentials and relevant opportunities of these concepts are discussed, their potential realization and the underlying technology required to verify these phenomena are reviewed with an emphasis on the material aspects involved. Finally, these solutions are compared with other popular cloaking techniques.     

Using photon funnels based on metamaterial cloaks to compress electromagnetic wave beams

Based on the metamaterial cloaking technique, we propose the use of a new photon funnel to compress a plane electromagnetic (EM) wave. The theoretical analysis and numerical simulations indicate that the compression ratio can be designed optionally and the compressed wave beam remains the original wave shape without any distortions. Here we apply the method to EM waves but it can be applied to acoustic waves and other fields as well.     

Phase‐Modulated Scattering Manipulation for Exterior Cloaking in Metal–Dielectric Hybrid Metamaterials

Artificially structured metamaterials with metallic or dielectric inclusions are extensively studied for exotic light manipulations via controlling the local‐resonant modes in the microstructures. The coupling between these resonant modes has drawn growing interest in recent years due to the advanced functional metamaterial making the microstructures more and more complex. Here, the suppression of magnetic resonance of a dielectric cuboid, an analogue to the scattering cancellation effect or radiation control system, realized with an exterior cloaking in a hybrid metamaterial system, is demonstrated. Furthermore, the significant modulation of the absorption of the dielectric resonator in the hybrid metamaterial is also demonstrated. The physical insight of the experimental results is well illuminated with a classical double‐harmonic‐oscillator model, from which it is revealed that the complex coupling, i.e., the phase of coupling coefficient, plays a crucial role in the overall response of the metal–dielectric hybrid system. The proposed design strategy is anticipated to form a more straightforward and efficient paradigm for practical applications based on radiation control via versatile mode couplings.     

Single and multilayer metamaterials fabricated by nanoimprint lithography

We demonstrate for the first time a fast and easy nanoimprint lithography (NIL) based stacking process of negative index structures like fishnet and Swiss-cross metamaterials. The process takes a few seconds, is cheap and produces three-dimensional (3D) negative index materials (NIMs) on a large area which is suitable for mass production. It can be performed on all common substrates even on flexible plastic foils. This work is therefore an important step toward novel and breakthrough applications of NIMs such as cloaking devices, perfect lenses and magnification of objects using NIM prisms. The optical properties of the fabricated samples were measured by means of transmission and reflection spectroscopy. From the measured data we retrieved the effective refractive index which is shown to be negative for a wavelength around 1.8 μm for the fishnet metamaterial while the Swiss-cross metamaterial samples show a distinct resonance at wavelength around 1.4 μm.