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排序方式: 共有550条查询结果,搜索用时 156 毫秒
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High‐Quality,Ultraconformal Aluminum‐Doped Zinc Oxide Nanoplasmonic and Hyperbolic Metamaterials 下载免费PDF全文
Conor T. Riley Joseph S. T. Smalley Kirk W. Post Dimitri N. Basov Yeshaiahu Fainman Deli Wang Zhaowei Liu Donald J. Sirbuly 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(7):892-901
Aluminum‐doped zinc oxide (AZO) is a tunable low‐loss plasmonic material capable of supporting dopant concentrations high enough to operate at telecommunication wavelengths. Due to its ultrahigh conformality and compatibility with semiconductor processing, atomic layer deposition (ALD) is a powerful tool for many plasmonic applications. However, despite many attempts, high‐quality AZO with a plasma frequency below 1550 nm has not yet been realized by ALD. Here a simple procedure is devised to tune the optical constants of AZO and enable plasmonic activity at 1550 nm with low loss. The highly conformal nature of ALD is also exploited to coat silicon nanopillars to create localized surface plasmon resonances that are tunable by adjusting the aluminum concentration, thermal conditions, and the use of a ZnO buffer layer. The high‐quality AZO is then used to make a layered AZO/ZnO structure that displays negative refraction in the telecommunication wavelength region due to hyperbolic dispersion. Finally, a novel synthetic scheme is demonstrated to create AZO embedded nanowires in ZnO, which also exhibits hyperbolic dispersion. 相似文献
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Metamaterials: A New Ba0.6Sr0.4TiO3–Silicon Hybrid Metamaterial Device in Terahertz Regime (Small 19/2016) 下载免费PDF全文
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Yao Chen Wangjie Ye Pan Shi Ruoqi He Jinbing Liang Jian Feng Pooya Sareh 《Advanced Engineering Materials》2023,25(16):2201762
Origami-based metamaterials have widespread application prospects in various industries including aerospace, automotive, flexible electronics, and civil engineering structures. Among the wide range of origami patterns, the fourfold tessellation known as Miura-ori is of particular attraction to engineers and designers. More specifically, researchers have proposed different 3D structures and metamaterials based on the geometric characteristics of this classic origami pattern. Herein, a computational modeling approach for the design and evaluation of 3D cellular solids with the Miura-ori metamaterial geometry which can be of zero or nonzero thicknesses is presented. To this end, first, a range of design alternatives generated based on a numerical parametric model is designed. Next, their mechanical properties and failure behavior under quasistatic axial compressive loads along three perpendicular directions are analyzed. Then, the effects of various geometric parameters on their energy absorption behavior under compression in the most appropriate direction are investigated. The findings of this study provide a basis for future experimental investigations and the potential application of such cellular solids for energy-absorbing purposes. 相似文献
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Acoustic metamaterials (AMs) for sound wave manipulation have attracted significant attention due to their fascinating functionalities, such as anomalous reflection/refraction, acoustic cloaking, sound absorption, acoustic imaging, etc. The acoustic phase-gradient metamaterials possess the capability of wavefront manipulation, thus, are fundamental to designing these fascinating functionalities. The underlying mechanism is controlling the acoustic responses (the phase and/or amplitude) of the units by varying the parameters so that one can redirect the wavefront in the desired manner. In this article, we review the state-of-the-art on development of phase-gradient metamaterials for wavefront manipulation. The governing principles of the phase-gradient metamaterials for wave control in static and moving media are first introduced. Then, according to the unit type, the phase-gradient metamaterials are roughly classified into three categories: the locally resonant structures, the space-coiling structures and the material-filling structures. Afterwards, three representative functionalities of the gradient metamaterials are reviewed, including acoustic cloaking, sound absorption/isolation and acoustic lens. Finally, the limitations of present metamaterials and possible future directions for development are concluded. 相似文献
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Yongdong Jin 《Advanced materials (Deerfield Beach, Fla.)》2012,24(38):5153-5165
The fields of biosensing and nanomedicine have recently witnessed an explosion of interest and progress in the design and study of plasmonic Au nanostructures (p‐AuNSs) or metamaterials geared towards a broad range of biological and biomedical applications. Due to their tunable and versatile plasmonic properties, such artificially engineered p‐AuNSs and materials have the potential to push biosensor sensitivity towards the single‐molecule detection limit, enabling new bioimaging modalities and new analytical techniques and tools capable of single‐molecule detection, analysis and manipulation, and to revolutionize the diagnosis and treatment of many diseases, including cancers. This report summarizes and highlights recent major advances in the emerging field of bioapplication‐oriented engineering of p‐AuNSs and hybrids, focusing on design considerations and ways to carry them out. A brief overview of the optical properties of p‐AuNSs is introduced, and then the importance of plasmonic engineering and future promising research directions and challenges in the field are discussed. 相似文献
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Vignolini S Yufa NA Cunha PS Guldin S Rushkin I Stefik M Hur K Wiesner U Baumberg JJ Steiner U 《Advanced materials (Deerfield Beach, Fla.)》2012,24(10):OP23-OP27
Optical metamaterials have unusual optical characteristics that arise from their periodic nanostructure. Their manufacture requires the assembly of 3D architectures with structure control on the 10-nm length scale. Such a 3D optical metamaterial, based on the replication of a self-assembled block copolymer into gold, is demonstrated. The resulting gold replica has a feature size that is two orders of magnitude smaller than the wavelength of visible light. Its optical signature reveals an archetypal Pendry wire metamaterial with linear and circular dichroism. 相似文献