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Reconfigurable Electromagnetics Through Metamaterials International Journal of Antennas and Propagation Reconfigurable Electromagnetics through Metamaterials Guest Editors: Giacomo Oliveri, Douglas Werner, Filiberto Bilotti, and Christophe Craeye Reconfigurable Electromagnetics through Metamaterials International Journal of Antennas and Propagation Reconfigurable Electromagnetics through Metamaterials Guest Editors: Giacomo Oliveri, Douglas Werner, Filiberto Bilotti, and Christophe Craeye Copyright © 2014 Hindawi Publishing Corporation. All rights reserved. This is a special issue published in “International Journal of Antennas and Propagation.” All articles are open access articles distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, pro- vided the original work is properly cited. Editorial Board Mohammod Ali, USA Se-Yun Kim, Republic of Korea Matteo Pastorino, Italy Charles Bunting, USA Ahmed A. Kishk, Canada Massimiliano Pieraccini, Italy Felipe Catedra,´ Spain Selvan T. Krishnasamy, India Sembiam R. Rengarajan, USA Dau-Chyrh Chang, Taiwan Ju-Hong Lee, Taiwan Ahmad Safaai-Jazi, USA Deb Chatterjee, USA Byungje Lee, Republic of Korea Safieddin Safavi-Naeini, Canada Z. N. Chen, Singapore Joshua Le-Wei Li, China Magdalena Salazar-Palma, Spain Michael Yan Wah Chia, Singapore J.S. Mandeep, Malaysia Stefano Selleri, Italy Shyh-Jong Chung, Taiwan Atsushi Mase, Japan Zhongxiang Shen, Singapore Lorenzo Crocco, Italy Giuseppe Mazzarella, Italy John J. Shynk, USA TayebA.Denidni,Canada C. F. Mecklenbrauker,¨ Austria Seong-Youp Suh, USA Francisco Falcone, Spain Mark Mirotznik, USA Parveen Wahid, USA Miguel Ferrando Bataller, Spain A. S. Mohan, Australia Yuanxun Ethan Wang, USA Vincenzo Galdi, Italy P. Mo h a n a n , In d i a Tat Soon Yeo, Singapore Wei Hong, China Pavel Nikitin, USA Young Jo ong Yo on, Korea Tamer S. Ibrahim, USA Symeon Nikolaou, Cyprus Jong-Won Yu, Republic of Korea Nemai Karmakar, Australia A. D. Panagopoulos, Greece Anping Zhao, China Contents Reconfigurable Electromagnetics through Metamaterials, Giacomo Oliveri, Douglas Werner, Filiberto Bilotti, and Christophe Craeye Volume2014,ArticleID215394,2pages Bandwidth Reconfigurable Metamaterial Arrays, Nathanael J. Smith, Dimitris Papantonis, and John L. Volakis Volume2014,ArticleID397576,17pages Reconfigurable and Tunable Metamaterials: A Review of the Theory and Applications, Jeremiah P. Turpin, Jeremy A. Bossard, Kenneth L. Morgan, Douglas H. Werner, and Pingjuan L. Werner Volume 2014, Article ID 429837, 18 pages MEMS-Reconfigurable Metamaterials and Antenna Applications,TomislavDebogovicand Julien Perruisseau-Carrier Volume 2014, Article ID 138138, 8 pages Switchable Electromagnetic Bandgap Surface Wave Antenna,QiangBai,KennethL.Ford, and Richard J. Langley Volume2014,ArticleID693852,7pages Tunable Plasmonic and Hyperbolic Metamaterials Based on Enhanced Nonlinear Response, Christos Argyropoulos, Francesco Monticone, Nasim Mohammadi Estakhri, and Andrea Alu` Volume 2014, Article ID 532634, 11 pages Voltage Controlled Intertwined Spiral Arrays for Reconfigurable Metasurfaces, A. Vallecchi, R.J.Langley,andA.G.Schuchinsky Volume 2014, Article ID 171637, 10 pages Mechanically Reconfigurable Microstrip Lines Loaded with Stepped Impedance Resonators and Potential Applications,J.NaquiandF.Mart´ın Volume 2014, Article ID 346838, 8 pages Hindawi Publishing Corporation International Journal of Antennas and Propagation Volume 2014, Article ID 215394, 2 pages http://dx.doi.org/10.1155/2014/215394 Editorial Reconfigurable Electromagnetics through Metamaterials Giacomo Oliveri,1 Douglas Werner,2 Filiberto Bilotti,3 and Christophe Craeye4 1 ELEDIA Research Center@DISI, University of Trento, 38123 Trento, Italy 2 Department of Electrical Engineering, The Pennsylvania State University, University Park, PA 16802, USA 3 Department of Engineering, Roma Tre University, 00146 Rome, Italy 4 Ecole Polytechnique de Louvain, Universite´ catholique de Louvain, 1348 Louvain-la-Neuve, Belgium Correspondence should be addressed to Giacomo Oliveri; [email protected] Received 17 April 2014; Accepted 17 April 2014; Published 15 June 2014 Copyright © 2014 Giacomo Oliveri et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. In recent years there has been a growing interest in the technological, methodological, and experimental viewpoint, development of artificial materials, in particular in meta- and it highlights some of the potentialities and future trends materials, engineered in order to exhibit electromagnetic in this research area. properties that do not occur in nature. The high degree More in detail, the paper by J. P. Turpin et al. presents a of enthusiasm over electromagnetic metamaterials stems comprehensive review of the developments of reconfigurable from their ability to manipulate and channel electromag- andtunablemetamaterialsaswellasoftheapplicationsof netic waves in unprecedented ways, which is derived from such technology. A survey of several different tuning meth- their subwavelength structure/granularity, rather than being ods, including circuit-enabled tuning, geometrical tuning, based solely on their constitutive materials. These features and material tuning, is presented, and their applicability over of electromagnetic metamaterials promise a path toward different frequency bands (from RF to optical frequencies) completely new devices with properties and functionality is discussed. A set of applications is also reported that com- not possible with currently available technologies. This is prises tunable filters and antennas, devices with adjustable specifically true whenever reconfigurability is of interest scattering parameters, tunable GRIN lenses, and antennas (e.g., for nonconventional and transformative applications with reconfigurable propagation features. Additionally, some in telecommunications, medicine, and security). Indeed, due of the open challenges towards their applicability in practical to their intrinsic structure, electromagnetic metamaterials devices are discussed. represent a key tool to implement the “reconfigurable electro- Areviewofsomeoftherecentcontributionstomaterials magnetics” paradigm that is to design and fabricate devices where the dynamic control is enabled by micro-electro- which can be controlled through a change of the physical mechanical systems (MEMS) technology is presented in the properties of their constitutive materials at a subwavelength paperbyT.DebogovicandJ.Perruisseau-Carrier.More scale. specifically, efficient reconfigurable phase shifters and leaky- In this framework, the special issue is aimed at reviewing wave antennas (LWA) based on reconfigurable composite the most recent advances of metamaterials as an enabling right/left-handed transmission lines are illustrated. More- technology for the design and realization of reconfigurable over, very low loss metasurface designs with reconfigurable devices at RF and THz/optical frequencies, and it includes reflection properties are discussed along with their applica- 7 papers representing the state-of-the-art work being car- tion in reflectarrays and partially reflective surfaces. Fabrica- ried out in this topic area by some of the top university tion and experimental validation of the presented devices in research labs around the world. This collection provides a theX-andKu-bandsarealsoreported. comprehensive overview of some of the most interesting N. J. Smith et al. present a conformal wideband meta- advancements in reconfigurable metamaterials from the material array achieving a 10 : 1 continuous bandwidth. To 2 International Journal of Antennas and Propagation accomplish this goal, a wideband Marchand-type balun the authors for their patience with us and with the review spanning the bandwidth from 280 MHz to 2800 MHz was process. We hope that you will find this special issue on designed and measured; its reconfiguration capabilities are the subject of reconfigurable electromagnetics interesting. obtained by means of circuit changes in the balanced The work reported in these manuscripts demonstrates that feed integrated with the wideband metamaterial array. The such a topic represents an extremely active interdisciplinary potentialities of the metamaterial array’s reconfiguration are research field with the promise of significant scientific and demonstrated through five example bandpass and band- industrial opportunities. rejection responses. ThepaperbyJ.NaquiandF.Martinisconcernedwith Giacomo Oliveri the exploitation of microstrip transmission lines loaded with Douglas Werner stepped impedance resonators (SIRs) etched on top of a signal Filiberto Bilotti strip to achieve mechanically reconfigurable metamaterials. Christophe Craeye More in detail, it is shown that the notch frequency and depth of the transmission line can be mechanically controlled by acting on the symmetry of the transmission line itself. Such a property is then exploited for the implementation of sensors and electronic barcodes. An innovative surface wave antenna is presented in the paper by Q. Bai et al. More in detail, the novel low-profile switchable antenna is based on band gap materials that can support both surface waves and normal modes of communi- cation. The techniques for generating a dual mode switchable antenna are reported, and the performance of the antenna is investigated. The surface
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