Bibliographies thématiques / Active metasurface

Littérature scientifique sur le sujet « Active metasurface »

Auteur : Grafiati

Publié le 1 juin 2024

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Articles de revues sur le sujet "Active metasurface"

Timpu, Flavia, Helena Weigand, Fabian Kaufmann, Felix U. Richter, Viola-Valentina Vogler-Neuling, Artemios Karvounis et Rachel Grange. « Towards active electro-optic lithium niobate metasurfaces ». EPJ Web of Conferences 238 (2020) : 05003. http://dx.doi.org/10.1051/epjconf/202023805003.

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We present the design and fabrication advances on active lithium niobate metasurfaces. We determine by numerical calculations a metasurface design with electro-magnetic resonances in the visible and near-infrared, by taking into account the constraints for fabrication on thin films of lithium niobate. We suggest that the optical properties of the metasurface can be switched using the electro-optical properties of lithium niobate.

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Curwen, Christopher A., Mohammad Shahili, Sadhvikas J. Addamane, John L. Reno, Boris S. Karasik, Benjamin S. Williams et Jonathan H. Kawamura. « Measurement of amplification and absorption of a THz quantum-cascade metasurface free-space amplifier ». AIP Advances 12, n^o 11 (1 novembre 2022) : 115205. http://dx.doi.org/10.1063/5.0122154.

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An active amplifying metasurface based on a quantum-cascade gain material at 2.7 THz is studied. The metasurface is first evaluated as the active component of an external cavity laser with excellent beam quality and frequency tunability from 2.55–2.8 THz. Amplification and absorption of the metasurface alone are then separately measured at a single frequency using a probe signal from a CO2-pumped gas laser operating at 2.743 THz. The metasurface reflectance vs bias is measured and compared with expectations from non-equilibrium Green’s function simulations of the quantum-cascade gain material and FEM simulations of the metasurface reflectance. A peak amplification on the order of 0.3 dB is measured. Design strategies are discussed for increasing single-reflection amplification (upward of 10 dB) and reducing power dissipation. Further increased amplification could be achieved by cascading multiple metasurfaces.

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Lin, Bizun, Jingru Li, Wei Lin et Qingfen Ma. « Active Tunable Elastic Metasurface for Abnormal Flexural Wave Transmission ». Applied Sciences 14, n^o 7 (24 mars 2024) : 2717. http://dx.doi.org/10.3390/app14072717.

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An active elastic metasurface has more flexibility than a passively modulated elastic metasurface, owing to the manipulation of the phase gradient that can be realized without changing the geometrical configuration. In this study, a negative proportional feedback control system was employed to provide positive active control stiffness for adaptive unit cells, with the aim of achieving the active modulation of the phase gradient. The relationship between the control gain and the phase velocity of the flexural wave was derived, and the transfer coefficients and phase shifts of the flexural wave through the adaptive unit cells were resolved using the transfer matrix method. Finite element simulations for wave propagations in the adaptive unit cells were conducted, and they verified the analytic solutions. Based on this theoretical and numerical work, we designed active elastic metasurfaces with adaptive unit cells with sub-wavelength thicknesses according to the generalized Snell’s law. These metasurfaces show flexibility in achieving abnormal functions for transmitted waves, including negative refraction and wave focusing, and transforming guided waves at different operating frequencies by manipulating the control gain. Therefore, the proposed active metasurface has great potential in the fields of the tunable manipulation of elastic waves and the design of smart devices.

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Meng, Qi, Xingqiao Chen, Wei Xu, Zhihong Zhu, Xiaodong Yuan et Jianfa Zhang. « High Q Resonant Sb2S3-Lithium Niobate Metasurface for Active Nanophotonics ». Nanomaterials 11, n^o 9 (13 septembre 2021) : 2373. http://dx.doi.org/10.3390/nano11092373.

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Phase change materials (PCMs) are attracting more and more attentions as enabling materials for tunable nanophotonics. They can be processed into functional photonic devices through customized laser writing, providing great flexibility for fabrication and reconfiguration. Lithium Niobate (LN) has excellent nonlinear and electro-optical properties, but is difficult to process, which limits its application in nanophotonic devices. In this paper, we combine the emerging low-loss phase change material Sb2S3 with LN and propose a new type of high Q resonant metasurface. Simulation results show that the Sb2S3-LN metasurface has extremely narrow linewidth of 0.096 nm and high quality (Q) factor of 15,964. With LN as the waveguide layer, strong nonlinear properties are observed in the hybrid metasurface, which can be employed for optical switches and isolators. By adding a pair of Au electrodes on both sides of the LN, we can realize dynamic electro-optical control of the resonant metasurface. The ultra-low loss of Sb2S3, and its combination with LN, makes it possible to realize a new family of high Q resonant metasurfaces for actively tunable nanophotonic devices with widespread applications including optical switching, light modulation, dynamic beam steering, optical phased array and so on.

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Ma, Qian, Qiao Ru Hong, Xinxin Gao, Qiang Xiao, Lei Chen et Tie Jun Cui. « Highly integrated programmable metasurface for multifunctions in reflections and transmissions ». APL Materials 10, n^o 6 (1 juin 2022) : 061113. http://dx.doi.org/10.1063/5.0093424.

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Programmable manipulations on both reflections and transmissions usually require multi-layer metasurfaces, numerous active components, and control circuits, leading to a larger profile, complicated bias circuit design, and higher cost. To address this problem, we present a highly integrated multifunctional metasurface for programmable reflections and transmissions using a single-layer metasurface and a single active component in each element. We design a multi-channel switchable structure, dominated by a single-pole triple-throw switcher, to alternatively achieve the 1-bit reflection-phase programmable modulations, total reflection, absorption, and transmission. Benefitting from the highly integrated packaging of the switcher chip and meta-structures, our scheme significantly reduces the design difficulty and improves the composite performance. The experimental results validate the capability of the proposed metasurface in realizing the multiple functions in a programmable way using the simple structure and control circuit. We believe that our design could further enrich the design methods of metasurfaces and provide new functions for information devices and systems.

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Effah, Elijah, Ezekiel Edward Nettey-Oppong, Ahmed Ali, Kyung Min Byun et Seung Ho Choi. « Tunable Metasurfaces Based on Mechanically Deformable Polymeric Substrates ». Photonics 10, n^o 2 (23 janvier 2023) : 119. http://dx.doi.org/10.3390/photonics10020119.

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The emergence of metamaterials has presented an unprecedented platform to control the fundamental properties of light at the nanoscale. Conventional metamaterials, however, possess passive properties that cannot be modulated post-fabrication, limiting their application spectrum. Recent metasurface research has explored a plethora of active control mechanisms to modulate the optical properties of metasurfaces post-fabrication. A key active control mechanism of optical properties involves the use of mechanical deformation, aided by deformable polymeric substrates. The use of deformable polymeric substrates enables dynamic tuning of the optical properties of metasurfaces including metalenses, metaholograms, resonance, and structural colors, which are collectively relevant for biosensing and bioimaging. Deformable–stretchable metasurfaces further enable conformable and flexible optics for wearable applications. To extend deformable–stretchable metasurfaces to biocompatible metasurfaces, a fundamental and comprehensive primer is required. This review covers the underlying principles that govern the highlighted representative metasurface applications, encompassing stretchable metalenses, stretchable metaholograms, tunable structural colors, and tunable plasmonic resonances, while highlighting potential advancements for sensing, imaging, and wearable biomedical applications.

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Yang, Jingyi, Sudip Gurung, Subhajit Bej, Peinan Ni et Ho Wai Howard Lee. « Active optical metasurfaces : comprehensive review on physics, mechanisms, and prospective applications ». Reports on Progress in Physics 85, n^o 3 (1 mars 2022) : 036101. http://dx.doi.org/10.1088/1361-6633/ac2aaf.

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Abstract Optical metasurfaces with subwavelength thickness hold considerable promise for future advances in fundamental optics and novel optical applications due to their unprecedented ability to control the phase, amplitude, and polarization of transmitted, reflected, and diffracted light. Introducing active functionalities to optical metasurfaces is an essential step to the development of next-generation flat optical components and devices. During the last few years, many attempts have been made to develop tunable optical metasurfaces with dynamic control of optical properties (e.g., amplitude, phase, polarization, spatial/spectral/temporal responses) and early-stage device functions (e.g., beam steering, tunable focusing, tunable color filters/absorber, dynamic hologram, etc) based on a variety of novel active materials and tunable mechanisms. These recently-developed active metasurfaces show significant promise for practical applications, but significant challenges still remain. In this review, a comprehensive overview of recently-reported tunable metasurfaces is provided which focuses on the ten major tunable metasurface mechanisms. For each type of mechanism, the performance metrics on the reported tunable metasurface are outlined, and the capabilities/limitations of each mechanism and its potential for various photonic applications are compared and summarized. This review concludes with discussion of several prospective applications, emerging technologies, and research directions based on the use of tunable optical metasurfaces. We anticipate significant new advances when the tunable mechanisms are further developed in the coming years.

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Li, Yuan, He Ma, Yu Wang, Jun Ding, Limei Qi, Yulan Fu, Ran Ning, Lu Rong, Dayong Wang et Xinping Zhang. « Electrically driven active VO₂/MXene metasurface for the terahertz modulation ». Applied Physics Letters 121, n^o 24 (12 décembre 2022) : 241902. http://dx.doi.org/10.1063/5.0129197.

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With the growing demand for broadband wireless communication, high-resolution radar, security inspection, and biological analysis, terahertz (THz) technology has made significant progress in recent years. The wide applications of THz technology benefited from the rapid development of various THz functional devices. Metasurface, an essential means of manipulating THz waves, has widely been applied in multiple THz functional devices. However, it is still a great challenge to construct flexible THz metasurface devices due to the lack of flexibility of traditional semiconductor and metal materials. In this work, a two-dimensional material, MXene, is used to prepare flexible metasurfaces with frequency filtering and polarization functions. By further combining with the phase-transition-material vanadium dioxide, the VO2/MXene metasurface exhibits good performance in amplitude modulation under electrical stimulation. The modulation depth of the device reaches 86% under a lower trigger power of 11.6 mW/mm2 and the response time is only ∼100 ms. Such a flexible active metasurface with superior performance and high integration will be useful in THz imaging systems, THz sensing systems, etc.

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Zhou, Hongqiang, Yongtian Wang, Xiaowei Li, Qing Wang, Qunshuo Wei, Guangzhou Geng et Lingling Huang. « Switchable active phase modulation and holography encryption based on hybrid metasurfaces ». Nanophotonics 9, n^o 4 (11 mars 2020) : 905–12. http://dx.doi.org/10.1515/nanoph-2019-0519.

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AbstractMetasurfaces are planar devices containing delicately designed nanoantenna or resonator arrays that allow for beam shaping, super resolution imaging, and holography. Hybrid metasurface – by integrating with tunable materials such as two-dimensional materials and phase change materials (PCMs) – provides a potential platform for active modulation of wavefronts. Specifically, PCMs can flexibly switch between crystalline and amorphous states with nonvolatile property under external stimuli and provide a large refractive permittivity contrast. Using metasurfaces based on PCM to manipulate wavefronts may provide new opportunities for switchable functionalities. Here, we propose two types of metasurface devices based on whole PCM films to realize switchable holography and simultaneous phase and interference encryption. This feature can be used to encrypt information in a switched state and store camouflage information in the other state by simply applying external thermal stimuli to the entire metasurface. This method can be applied in areas such as beam shaping, optical encryption, and anti-counterfeiting.

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Chang, Shengyuan, Xuexue Guo et Xingjie Ni. « Optical Metasurfaces : Progress and Applications ». Annual Review of Materials Research 48, n^o 1 (juillet 2018) : 279–302. http://dx.doi.org/10.1146/annurev-matsci-070616-124220.

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A metasurface is an artificial nanostructured interface that has subwavelength thickness and that manipulates light by spatially arranged meta-atoms—fundamental building blocks of the metasurface. Those meta-atoms, usually consisting of plasmonic or dielectric nanoantennas, can directly change light properties such as phase, amplitude, and polarization. As a derivative of three-dimensional (3D) metamaterials, metasurfaces have been emerging to tackle some of the critical challenges rooted in traditional metamaterials, such as high resistive loss from resonant plasmonic components and fabrication requirements for making 3D nanostructures. In the past few years, metasurfaces have achieved groundbreaking progress, providing unparalleled control of light, including constructing arbitrary wave fronts and realizing active and nonlinear optical effects. This article provides a systematic review of the current progress in and applications of optical metasurfaces, as well as an overview of metasurface building blocks based on plasmonic resonances, Mie resonance, and the Pancharatnam-Berry phase.

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Thèses sur le sujet "Active metasurface"

Mello, Rafael Gonçalves Licursi de. « Active and passive metasurfaces : methodology for the design of a low profile, beam-steerable, multiband, and wideband antenna ». Electronic Thesis or Diss., Institut polytechnique de Paris, 2022. http://www.theses.fr/2022IPPAT025.

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Les métasurfaces sont des matériaux artificiels qui peuvent être combinés avec des éléments micro-ondes traditionnels dans des solutions révolutionnaires. Les recherches sur l'utilisation des métasurfaces dans les rôles de réflecteur et/ou de superstrat d'antenne se sont considérablement intensifiées à partir du début des années 2020, en raison de leurs fonctionnalités innovantes alignées avec les dernières tendances en Télécommunications. Dans cette thèse, des méthodologies pour l'utilisation de métasurfaces passives et actives dans la conception d'antennes sont présentées. Une première méthodologie qui exploite à la fois les comportements proches du conducteur électrique parfait (CEP) et du conducteur magnétique parfait (CMP) d'un conducteur magnétique artificiel (CMA) bi-bande est utilisée pour concevoir une antenne directive multibande à faible encombrement. Cette méthodologie est validée avec un prototype pour les normes européennes 4G/5G et Wi-Fi 2.4/5/6E, fonctionnant dans les bandes suivantes : 2.40–2.70 GHz, 3.40–3.80 GHz, 5.17–5.83 GHz, and 5.93–6.45 GHz. De plus, une méthodologie pour gérer le mécanisme Fabry-Pérot dans une antenne composée d'une bow-tie avec les bords arrondis rainurés, d'un AMC passif bi-bande et d'une métasurface Huygens active multibande est présentée. Cette méthodologie est validée avec la conception d'une antenne multibande, directive, à faible encombrement qui effectue un dépointage du faisceau indépendant dans une des bandes de fréquences de fonctionnement. Grâce au contrôle des tensions de polarisation sur quatre colonnes de varactors dans la métasurface reconfigurable et multibande de Huygens, le faisceau peut être dynamiquement dépointé à ±51°, de manière continue, dans une gamme de fréquences comprise dans la gamme de fréquences 5G européenne (de 3.50 to 3.65 GHz). En même temps, les diagrammes de rayonnement concernant la 4G et le Wi-Fi 2.4/5/6E restent pratiquement inchangés
Metasurfaces are artificial engineered materials that can be combined with traditional microwave components in ground-breaking solutions. The research on the use of metasurfaces in the roles of antenna reflector and/or superstrate considerably increased mainly from the beginning of the 2020s, because of their innovative functionalities in line with the ultimate Telecommunication trends. In this thesis, methodologies for the use of passive and active metasurfaces in the design of antennas are presented. A first methodology which exploits both the near-perfect electric conductor (PEC) and near-perfect magnetic conductor (PMC) behaviors of a dual-band artificial magnetic conductor (AMC) is used to design a low-profile, multiband, directive antenna. This methodology is validated with a prototype suitable for the European standards of 4G/5G and Wi-Fi 2.4/5/6E, operating within the following bands: 2.40–2.70 GHz, 3.40–3.80 GHz, 5.17–5.83 GHz, and 5.93–6.45 GHz. Additionally, a methodology to handle the Fabry-Pérot mechanism in an antenna composed of a grooved rounded-edge bow-tie, a passive dual-band AMC, and an active multiband Huygens metasurface is presented. This methodology is validated with the design of a multiband, directive, low-profile, antenna that performs an independent beam-steering in only one of the operating frequency bands. Through the controlling of the bias voltages over four columns of varactors in the reconfigurable, multiband Huygens metasurface, the beam may be dynamically steered in ±51°, in a continuous manner, in a frequency range lying inside the European 5G frequency range (from 3.50 to 3.65 GHz. All at once, the radiation patterns concerning the 4G and Wi-Fi 2.4/5/6E keep practically unaffected

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Duran, Venegas Juan Antonio. « Reconfigurable Metasurfaces for Beam Scanning Planar Antennas ». Thesis, Toulouse, INPT, 2016. http://www.theses.fr/2016INPT0102.

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Nous étudions la mise en oeuvre d ‘antenne à balayage électronique dédiés aux applications de communications par satellite géostationnaire. Les structures développées sont adaptées pour être embarquées dans un avion ou un train. L'architecture de l'antenne développée est constituée d’un double réseau linéaire dans deux dimmensions transverses. Le balayage dans chaque réseau linéaire est assuré par des lignes coplanaires à métamateriaux contrôlées par varactor. Nous porposons de nouvelles méthodes de caracterisation des discontinuités en ligne coplanaire pour la conception de la ligne. De plus, un système de prélèvement d'énergie a dû être conçu afin d'alimenter des éléments rayonnants et testé avec différentes antennes patch. Enfin, nous envisageons la co-intégration des structures rayonnantes et des lignes CRLH ainsi que le contrôle électronique par les diodes
We are studying the implementation of 'Scanning Antenna dedicated to the applications of satellite communications geostationary. The structures developed are suitable for to be on board an airplane or a train. The architecture of the antenna developed consists of a double linear network in two transverse dimmensions. The scan in each network is provided by the lines coplanar to metamaterials controlled by varactor. We porposons of new methods characterization of discontinuities coplanar online for the line design. In addition, a energy harvesting system has be designed to feed radiating elements and tested with patch different antennas. Finally, we are considering co-integration radiating structures and CRLH lines as well as control electronic by the diodes

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Walter, Felicitas [Verfasser]. « Optical properties and encoding of information of nonlinear and active plasmonic metasurfaces / Felicitas Walter ». Paderborn : Universitätsbibliothek, 2018. http://d-nb.info/1171897685/34.

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Chen, Jie, et 陳婕. « Active gradient-phase metasurface based on phase-change material Ge2Sb2Te5 ». Thesis, 2015. http://ndltd.ncl.edu.tw/handle/51801850616860068037.

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碩士
國立臺灣大學
物理研究所
103
Metamaterial is a hot topic in these years which is applied to the researches of clocking, negative refraction, relying on its non-existing proprieties in nature. Metasurface is an important part connecting metamaterial with metadevice, contributing to a great many of applications, such as flat lens, metahologram and some meta-optical-component. Recently, Phase-change materials are applied to active metamaterial due to their distinctions in optical constant between crystal state and amorphous state. Ge2Sb2Te5 (GST) alloy is widely used in optical data storage, phase change memory and nanolithography owing to its nature of stability, quick response (femtosecond order) to external stimuli and dramatical difference in optical constant and electrical resistance between two phases. We present an active gradient-phase metasurface design based on algorithms of Finite Element Method (FEM) and Finite-Difference Time-Domain (FDTD). An active gradient-phase metasurface made of phase-change material exhibiting normal or abnormal reflection working at communication frequency (around 1550 nm) is achieved. When GST alloy nanostructures are all in crystal state, there is a normal reflective phenomenon following traditional laws. Under an external stimuli, an anomalous reflected beam can be detected in the angle of 19 or 40 degree off the traditional light path. The difference of the geometry and phase-state leads to a distinct phase delay. With a specific arrangement, the wavefront can be reshaped and the metasurfce give rise to an abnormal reflected phenomena. The phase-state of GST rods can be changed to attain a period variation of phase modulation by fs-laser process. In a word, there is a three-level phase modulation when elements are partly in amorphous and partly in crystal state. Here, we achieve a three-level phase modulation only relying on two different geometry by introducing phase-state of PCMs. Meanwhile, an active phase-gradient metasurface is realized to improve tunability of metamaterial which is potential for active metadevice in optical communication process. Key words: Metasurface, Phase-change materials, Active modulation

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Kwon, Hyounghan. « Dielectric Metasurfaces for Integrated Imaging Devices and Active Optical Elements ». Thesis, 2021.

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Optical dielectric metasurfaces have shown great advances in the last two decades and become promising candidates for next-generation free-space optical elements. In addition to their compatibility with scalable semiconductor fabrication technology, metasurfaces have provided new and efficient ways to manipulate diverse characteristics of light. In this thesis, we demonstrate the potential of dielectric metastructures in the realization of compact imaging devices, reconfigurable optical elements, and multi-layer inverse-designed metasurfaces. With the metasurfaces’ extreme capability to simultaneously control phase and polarization, we first showcase their potential toward optical field imaging applications. In this regard, we demonstrate a system of dielectric metasurfaces and designed random metasurfaces for single-shot phase gradient microscopes and computational complex field imaging system, respectively. Then, we propose nano-electromechanically tunable resonant dielectric metasurfaces as a general platform for active metasurfaces. For example, we demonstrate two different types of the phase and amplitude modulators. While one utilizes resonant eigenmodes in the lattice such as leaky guided mode resonances and bound-states in the continuum modes, the other is based on the high-Q Mie resonances in the dielectric nanostructures where symmetry is broken. In addition to the modulation of the phase and amplitude, we also show tuning of strong chiroptical responses in dielectric chiral metasurfaces. Next, we experimentally demonstrate inverse-designed multi-layer metasurfaces. Not only do they provide increased degree of freedom in the design space, but also overcome limits of conventional design methods of the metasurfaces. Finally, we summarize the presented works and conclude this thesis with a brief outlook on what aspects of the metasurfaces can be important for their real-world applications in the future and what challenges and opportunities remain.

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Xie, Zu-Wen, et 謝祖文. « Active plasmonic color filters of aluminum metasurfaces integrated with liquid crystals ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/j692j2.

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碩士
國立交通大學
照明與能源光電研究所
106
Designing color pixels using plasmonic nanostructures and metasurfaces has become a luring area of research in recent years. Here, we experimentally demonstrated the voltage tunability of a dynamic plasmonic color filter by using an aluminum grating integrated with the nematic liquid crystal (LC). Along with a typical substrate coated with rubbed polyimide film, the aluminum grating itself serves as a molecular alignment layer to form a twisted LC cell. This hybrid structure allows electrically controlled transmission and reflection color by applying a voltage. A significant spectral tunability of such a device has been demonstrated by applying a small voltage from 0 to 4 Vrms.

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Chen, Pai-Yen. « Nonlinear, passive and active inclusions to tailor the wave interaction in metamaterials and metasurfaces ». Thesis, 2013. http://hdl.handle.net/2152/23291.

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Metamaterials have experienced a rapid growth of interest over the past few years and new capabilities are being explored to broaden the range of their unique electromagnetic properties for functional devices, including tunable, switchable, and nonlinear properties. In the future, there is the prospect of opening even more exciting applications with metamaterials, not yet imagined and thought not to be possible with currently available techniques. In my dissertation, I discuss several solutions for passive and active metamaterials and metasurfaces, with a particular focus on their potential applications, enabling a new class of metamaterials in the spectral range from radio frequencies (RF) and microwaves, terahertz (THz) to visible light. First, I demonstrate that by loading plasmonic nanoantennas with nonlinear nanoparticles, the nonlinear optical processes, such as multiple wave mixing, high harmonic generation, phase conjugation and optical bistability may be realized at the nanoscale, thanks to the strongly enhanced optical near fields accompanied with the plasmonic resonance. I present here the design, practical realization, and homogenization theory of nonlinear optical metamaterials and metasurfaces formed by optical nanoantenna arrays loaded with nonlinearities. As an extreme case of light manipulation at the "atomic" scale, I also study the collective oscillation of massless Dirac fermions inside grapheme monolayers, in which surface plasmon polaritons are controlled by electrostatic gating. I present how a graphene monolayer may serve as a building block and design paradigm for adaptable, switchable and frequency-configurable THz metamaterials and nanodevices, realizing various functionalities for cloaking, sensing, absorbing, switching, modulating, phasing, filtering, impedance transformation, photomixing and frequency synthesis in the THz spectrum. Last I present various metamaterial designs applied to invisibility cloaks based on the scattering cancellation mechanism enabled by plasmonic materials and passive/active metamaterials and metasurfaces. This cloaking technology may be used for camouflaging, enhancing the sensitivity and signal-to-noise ratio in RF wireless communication and sensor networks. In addition, electrically-small antennas based on the phase compensation effect offered by metamaterials with low or negative material properties are presented, with tailorable modal frequencies, bandwidth, and radiation properties.
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Chapitres de livres sur le sujet "Active metasurface"

Zhao, Jiajun. « Manipulating Acoustic Focus with an Active Metasurface Piezoelectric Transducer ». Dans Manipulation of Sound Properties by Acoustic Metasurface and Metastructure, 31–41. Singapore : Springer Singapore, 2016. http://dx.doi.org/10.1007/978-981-10-2125-1_4.

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Xu, He-Xiu, Shiwei Tang, Tong Cai, Shulin Sun, Qiong He et Lei Zhou. « Linearly Polarized Active Multifunctional Metasurfaces ». Dans Multifunctional Metasurfaces, 93–121. Cham : Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-031-02390-3_5.

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Michael Wu, Chung-Tse, et Pai-Yen Chen. « Low-Profile Metamaterial-Based Adaptative Beamforming Techniques ». Dans Modern Printed-Circuit Antennas. IntechOpen, 2020. http://dx.doi.org/10.5772/intechopen.90012.

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In this chapter, we will review recent research advances on beamforming and spatial multiplexing techniques using reconfigurable metamaterials (MTMs) and metasurfaces. This chapter starts by discussing basic principles and practical applications of transmission line-based metamaterials and planar metasurfaces, followed by their active versions that enable novel smart antennas with beam steering and beamshaping functions. We include detailed descriptions of their practical realizations and the integration with circuits and the radio-frequency (RF) frontend, which are used to adaptively and dynamically manipulate electromagnetic radiation. We summarize the state-of-the-art MTM/metasurface-based beamforming techniques and provide a critical comparison for their uses in the RF-to-millimeter-wave range in terms of cost, reconfigurability, system integratability and radiation properties. These techniques are expected to pave the way for the massive deployment of communication, radar, remote sensing and medical and security imaging systems.

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Sharma, Anuj Kumar, et Vipul Sharma. « Active and Passive Metamaterials and Metasurfaces ». Dans Advances in Wireless Technologies and Telecommunication, 297–319. IGI Global, 2023. http://dx.doi.org/10.4018/978-1-6684-8287-2.ch012.

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The authors of this chapter begin by discussing the fundamentals of metamaterials and metasurfaces before moving on to active and passive metamaterials. This chapter is broken up into six different sections. In the first section, an overview of metamaterials and metasurfaces is provided, and in the second half, active and passive metamaterials and metasurfaces are discussed. This is followed by an explanation of active metamaterials and metasurfaces in part three, fabrication methods for metamaterials and metasurfaces in part four, future directions and challenges in the field of metamaterials in part five, and a conclusion in part six.

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Malek, Stephanie C., Adam C. Overvig, Sajan Shrestha et Nanfang Yu. « Active nonlocal metasurfaces ». Dans Frontiers in Optics and Photonics, 673–84. De Gruyter, 2021. http://dx.doi.org/10.1515/9783110710687-053.

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Kar, Subal. « Matamaterial-inspired passive components, antennas and active devices ». Dans Metamaterials and Metasurfaces, 3–1. IOP Publishing, 2023. http://dx.doi.org/10.1088/978-0-7503-5532-2ch3.

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Actes de conférences sur le sujet "Active metasurface"

Felbacq, Didier, Emmanuel Rousseau et Emmanuel Kling. « Topological excitations of a quantum metasurface ». Dans Active Photonic Platforms XI, sous la direction de Ganapathi S. Subramania et Stavroula Foteinopoulou. SPIE, 2019. http://dx.doi.org/10.1117/12.2528770.

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Chen, H. T. « Active terahertz metasurface devices ». Dans 2016 IEEE International Electron Devices Meeting (IEDM). IEEE, 2016. http://dx.doi.org/10.1109/iedm.2016.7838508.

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Zhang, Yan, Guocui Wang et Xinke Wang. « Active Terahertz Metasurface Devices ». Dans 2023 48th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz). IEEE, 2023. http://dx.doi.org/10.1109/irmmw-thz57677.2023.10299255.

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Felbacq, Didier, et Emmanuel Rousseau. « Strong light-matter coupling in a quantum metasurface ». Dans Active Photonic Platforms X, sous la direction de Ganapathi S. Subramania et Stavroula Foteinopoulou. SPIE, 2018. http://dx.doi.org/10.1117/12.2320277.

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Kafaie Shirmanesh, Ghazaleh, Ruzan Sokhoyan, Pin Chieh Wu et Harry A. Atwater. « Reconfigurable beam steering metasurface at telecommunication wavelengths (Conference Presentation) ». Dans Active Photonic Platforms X, sous la direction de Ganapathi S. Subramania et Stavroula Foteinopoulou. SPIE, 2018. http://dx.doi.org/10.1117/12.2320835.

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Zou, Chengjun, Purushottam Poudel, Katsuya Tanaka, Alexander Minovich, Thomas Pertsch, Felix H. Schacher et Isabelle Staude. « Multiresponsive dielectric metasurfaces with light-and temperature-responsive copolymers ». Dans CLEO : QELS_Fundamental Science. Washington, D.C. : Optica Publishing Group, 2022. http://dx.doi.org/10.1364/cleo_qels.2022.fm1b.6.

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We experimentally demonstrate multiresponsive tuning of high-quality-factor dielectric metasurfaces integrated with light- and temperature-responsive copolymers at near-infrared wavelengths. Our work explores multidimensional active control of metasurface-based nanophotonic systems for novel light field manipulations.

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Xu, HongXin, et Yong Jin Zhou. « Wideband transmission/absorption active metasurface ». Dans 2021 International Applied Computational Electromagnetics Society (ACES-China) Symposium. IEEE, 2021. http://dx.doi.org/10.23919/aces-china52398.2021.9581354.

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Yang, Guoce, Mengyun Wang, June Sang Lee, Nikolaos Farmakidis et Harish Bhaskaran. « Reconfigurable nonlocal metasurface based on phase change materials ». Dans Active Photonic Platforms (APP) 2023, sous la direction de Ganapathi S. Subramania et Stavroula Foteinopoulou. SPIE, 2023. http://dx.doi.org/10.1117/12.2675688.

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Wu, Pin Chieh. « Flat optics with nanophotonic metasurface ». Dans JSAP-OSA Joint Symposia. Washington, D.C. : Optica Publishing Group, 2019. http://dx.doi.org/10.1364/jsap.2019.18p_e208_1.

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Comprehensive light manipulation is highly desired in modem optics applications, such as LiDAR, augmented imaging system, and quantum technology. To tailor the light wavefront, the conventional optical components rely on the phase accumulation via the propagation length. It leads to the fact that the conventional optical components are physically bulky, but cannot simultaneously manage electromagnetic waves in different degrees of freedom either. Nanophotonic metasurfaces composed of artificial structures, enabling abrupt changes to the electromagnetic phase as well as amplitude within a subwavelength spatial region. Thus, they are very promising for the development of flat optics systems [1-3]. In this presentation, I will talk about unprecedented schemes with nanophotonic metasurfaces for optical modulation and related applications [4, 5], including broadband achromatic metalens (metasurface lens) for full-color imaging [6, 7] and active control of light properties in demand [8, 9].

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Smalley, Joseph S., Xuexin Ren, Jeong Yub Lee, Xiang Zhang, Sui Yang, Yuan Wang, Woong Ko et al. « Subwavelength pixelated CMOS color sensors based on Anti-Hermitian metasurface ». Dans Active Photonic Platforms XIII, sous la direction de Ganapathi S. Subramania et Stavroula Foteinopoulou. SPIE, 2021. http://dx.doi.org/10.1117/12.2595013.

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