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21.
Chameleons are masters of light, expertly changing their color, pattern, and reflectivity in response to their environment. Engineered materials that share this tunability can be transformative, enabling active camouflage, tunable holograms, and novel colorimetric medical sensors. While progress has been made in creating artificial chameleon skin, existing schemes often require external power, are not continuously tunable, and may prove too stiff or bulky for applications. Here, a chemically tunable, large‐area metamaterial is demonstrated that accesses a wide range of colors and refractive indices. An ordered monolayer of nanoresonators is fabricated, then its optical response is dynamically tuned by infiltrating its polymer substrate with solvents. The material shows a strong magnetic response with a dependence on resonator spacing that leads to a highly tunable effective permittivity, permeability, and refractive index spanning negative and positive values. The unity‐order index tuning exceeds that of traditional electro‐optic and photochromic materials and is robust to cycling, providing a path toward programmable optical elements and responsive light routing. 相似文献
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Yuan Hsing Fu Ai Qun Liu Wei Ming Zhu Xu Ming Zhang Din Ping Tsai Jing Bo Zhang Ting Mei Ji Fang Tao Hong Chen Guo Xin Hai Zhang Jing Hua Teng Nikolay I. Zheludev Guo Qiang Lo Dim Lee Kwong 《Advanced functional materials》2011,21(18):3589-3594
A micromachined reconfigurable metamaterial is presented, whose unit cell consists of a pair of asymmetric split‐ring resonators (ASRRs); one is fixed to the substrate while the other is patterned on a movable frame. The reconfigurable metamaterial and the supporting structures (e.g., microactuators, anchors, supporting frames, etc.) are fabricated on a silicon‐on‐insulator wafer using deep reactive‐ion etching (DRIE). By adjusting the distance between the two ASRRs, the strength of dipole–dipole coupling can be tuned continuously using the micromachined actuators and this enables tailoring of the electromagnetic response. The reconfiguration of unit cells endows the micromachined reconfigurable metamaterials with unique merits such as electromagnetic response under normal incidence and wide tuning of resonant frequency (measured as 31% and 22% for transverse electric polarization and transverse magnetic polarization, respectively). The reconfiguration could also allow switching between the polarization‐dependent and polarization‐independent states. With these features, the micromachined reconfigurable metamaterials may find potential applications in transformation optics devices, sensors, intelligent detectors, tunable frequency‐selective surfaces, and spectral filters. 相似文献
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分析复合左右手特异材料微带漏波天线的辐射原理,建立复合左右手材料微带漏波天线仿真模型,通过仿真计算得到微带漏波天线的辐射特性。制备与仿真参数相同的实物天线,测量天线S参数、方向图和天线各单元电容瞬态电压。最后,对仿真试验结果和实物天线测量结果比较,吻合较好。在固定工作频率下,复合左右手特异材料微带漏波天线工作在左手区时,电磁波辐射主要发生在天线结构前几个单元,且电磁波以指数形式快速衰减,工作在右手区时,电磁波沿整个天线辐射,且电磁波衰减较慢。 相似文献
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太赫兹波段电磁超介质的应用及研究进展 总被引:1,自引:0,他引:1
太赫兹波和电磁超介质是电磁学领域关注的热点.太赫兹波与电磁超介质相互作用可以实现对太赫兹波的操纵和调控,有望填补"太赫兹空白".介绍了太赫兹波段电磁超介质的研究进展,包括电磁超介质电磁性能可调谐的实施途径,电磁超介质在太赫兹功能器件方面的应用(调制器/开关、传感器/探测器、滤波器、偏振元件和吸波器),太赫兹波段表面等离... 相似文献
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Metamaterials: Nonlinear Superchiral Meta‐Surfaces: Tuning Chirality and Disentangling Non‐Reciprocity at the Nanoscale (Adv. Mater. 24/2014) 下载免费PDF全文
V. K. Valev J. J. Baumberg B. De Clercq N. Braz X. Zheng E. J. Osley S. Vandendriessche M. Hojeij C. Blejean J. Mertens C. G. Biris V. Volskiy M. Ameloot Y. Ekinci G. A. E. Vandenbosch P. A. Warburton V. V. Moshchalkov N. C. Panoiu T. Verbiest 《Advanced materials (Deerfield Beach, Fla.)》2014,26(24):3982-3982
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