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Shin DI, Kim J, Im SG, Kang T, Wang K, Lee G, Kwon SJ, Park S, Yi GR. Proximal High-Index Metamaterials based on a Superlattice of Gold Nanohexagons Targeting the Near-Infrared Band. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2405650. [PMID: 39169743 DOI: 10.1002/adma.202405650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2024] [Revised: 07/28/2024] [Indexed: 08/23/2024]
Abstract
Plasmonic nanoparticles can be assembled into a superlattice, to form optical metamaterials, particularly targeting precise control of optical properties such as refractive index (RI). The superlattices exhibit enhanced near-field, given the sufficiently narrow gap between nanoparticles supporting multiple plasmonic resonance modes only realized in proximal environments. Herein, the planar superlattice of plasmonic Au nanohexagons (AuNHs) with precisely controlled geometries such as size, shape, and edge-gaps is reported. The proximal AuNHs superlattice realized over a large area with selective edge-to-edge assembly exhibited the highest-ever-recorded RI values in the near-infrared (NIR) band, surpassing the upper limit of the RI of the natural intrinsic materials (up to 10.04 at λ = 1.5 µm). The exceptionally enhanced RI is derived from intensified in-plane surface plasmon coupling across the superlattices. Precise control of the edge-gap of neighboring AuNHs systematically tuned the RI as confirmed by numerical analysis based on the plasmonic percolation model. Furthermore, a 1D photonic crystal, composed of alternating layers of AuNHs superlattices and low-index polymers, is constructed to enhance the selectivity of the reflectivity operating in the NIR band. It is expected that the proximal AuNHs superlattices can be used as new optical metamaterials that can be extended to the NIR range.
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Affiliation(s)
- Dong-In Shin
- SKKU Advanced Institute of Nanotechnology (SAINT), Suwon, 16419, Republic of Korea
- Korea Basic Science Institute, Daejeon, 34133, Republic of Korea
| | - Jeongwon Kim
- Department of Chemistry, Sungkyunkwan University College of Natural Science, Suwon, 16419, Republic of Korea
| | - Seong-Gyun Im
- School of Chemical Engineering, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Taewoo Kang
- School of Chemical Engineering, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Ke Wang
- Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Nam-Gu, Pohang, 37673, Republic of Korea
- School of Materials Science and Engineering, Hubei University, Wuhan, Hubei, 430000, China
| | - Gaehang Lee
- Korea Basic Science Institute, Daejeon, 34133, Republic of Korea
| | - Seok Joon Kwon
- School of Chemical Engineering, Sungkyunkwan University, Suwon, 16419, Republic of Korea
- SKKU Institute of Energy Science & Technology (SIEST), Department of Semiconductor Convergence Engineering and Department of Future Energy Engineering, Sungkyunkwan University (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon, 16419, Republic of Korea
| | - Sungho Park
- Department of Chemistry, Yonsei University, Seoul, 03722, Republic of Korea
| | - Gi-Ra Yi
- Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Nam-Gu, Pohang, 37673, Republic of Korea
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2
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Falsi L, Macis S, Gelkop Y, Tartara L, Bonaventura E, Di Pietro P, Perucchi A, Garcia Y, Perepelitsa G, DelRe E, Agranat AJ, Lupi S. Anomalous Optical Properties of KTN:Li Ferroelectric Supercrystals. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:899. [PMID: 36903777 PMCID: PMC10005727 DOI: 10.3390/nano13050899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 02/10/2023] [Accepted: 02/23/2023] [Indexed: 06/18/2023]
Abstract
We report a spectroscopic investigation of potassium-lithium-tantalate-niobate (KTN:Li) across its room-temperature ferroelectric phase transition, when the sample manifests a supercrystal phase. Reflection and transmission results indicate an unexpected temperature-dependent enhancement of average index of refraction from 450 nm to 1100 nm, with no appreciable accompanying increase in absorption. Second-harmonic generation and phase-contrast imaging indicate that the enhancement is correlated to ferroelectric domains and highly localized at the supercrystal lattice sites. Implementing a two-component effective medium model, the response of each lattice site is found to be compatible with giant broadband refraction.
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Affiliation(s)
- Ludovica Falsi
- Dipartimento di Fisica, Università di Roma “La Sapienza”, 00185 Rome, Italy
| | - Salvatore Macis
- Dipartimento di Fisica, Università di Roma “La Sapienza”, 00185 Rome, Italy
| | - Yehonatan Gelkop
- The Department of Applied Physics, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Luca Tartara
- Dipartimento di Ingegneria Industriale e dell’Informazione, Università di Pavia, 27100 Pavia, Italy
| | | | - Paola Di Pietro
- Elettra—Sincrotrone Trieste S.C.p.A. S.S.14, Km 163.5 in AREA Science Park IT-34149 Basovizza, 34100 Trieste, Italy
| | - Andrea Perucchi
- Elettra—Sincrotrone Trieste S.C.p.A. S.S.14, Km 163.5 in AREA Science Park IT-34149 Basovizza, 34100 Trieste, Italy
| | - Yehudit Garcia
- The Department of Applied Physics, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Galina Perepelitsa
- The Department of Applied Physics, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Eugenio DelRe
- Dipartimento di Fisica, Università di Roma “La Sapienza”, 00185 Rome, Italy
- ISC-CNR, Università di Roma “La Sapienza”, 00185 Rome, Italy
| | - Aharon J. Agranat
- The Department of Applied Physics, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Stefano Lupi
- Dipartimento di Fisica, Università di Roma “La Sapienza”, 00185 Rome, Italy
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Karamirad M, Pouyanfar N, Alibakhshikenari M, Ghobadi C, Nourinia J, See CH, Falcone F. Low-loss and dual-band filter inspired by glide symmetry principle over millimeter-wave spectrum for 5G cellular networks. iScience 2022; 26:105899. [PMID: 36691624 PMCID: PMC9860387 DOI: 10.1016/j.isci.2022.105899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 11/28/2022] [Accepted: 12/22/2022] [Indexed: 12/28/2022] Open
Abstract
This paper focuses on designing a dual-band, bandpass filter configuration inspired by glide-symmetric structures in a single plane. Geometry configuration of elliptical slots on both sides of single substrate generally affects electromagnetic fields as well as rejection bands. Easy fabrication with misalignment avoidance during assembly procedure unlike conventional structures based on gap waveguide technology, make them appropriate to use in electromagnetic devices. Parametric study on dispersion characteristics is carried out in this article to find out how rejection-bands are offered through breaking the symmetry. A method for producing symmetry is also suggested, which may be helpful for reconfigurable devices. Moreover, equivalent circuit model is demonstrated to get insight of the mechanism of the presented glide symmetry scheme. The transmission frequency ranges of two passbands with center frequencies of 19.74 GHz and 28.233 GHz are shown by the measured and calculated S- parameters of five unit-cell structures.
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Affiliation(s)
- Mohsen Karamirad
- Department of Electrical Engineering, Urmia University, Urmia, Iran
| | - Negin Pouyanfar
- Department of Electrical Engineering, Urmia University, Urmia, Iran
| | - Mohammad Alibakhshikenari
- Department of Signal Theory and Communications, Universidad Carlos III de Madrid, Leganés, 28911 Madrid, Spain,Corresponding author
| | - Changiz Ghobadi
- Department of Electrical Engineering, Urmia University, Urmia, Iran
| | - Javad Nourinia
- Department of Electrical Engineering, Urmia University, Urmia, Iran
| | - Chan Hwang See
- School of Engineering and the Built Environment, Edinburgh Napier University, 10 Colinton Road, Edinburgh EH10 5DT, UK
| | - Francisco Falcone
- Department of Electric, Electronic and Communication Engineering and the Institute of Smart Cities, Public University of Navarre, and the Tecnologico de Monterrey, School of Engineering and Sciences, 31006 Pamplona, Spain
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4
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Viskadourakis Z, Grammatikakis K, Katsara K, Drymiskianaki A, Kenanakis G. Fabrication of Metasurfaces on Building Construction Materials for Potential Electromagnetic Applications in the Microwave Band. MATERIALS (BASEL, SWITZERLAND) 2022; 15:ma15207315. [PMID: 36295380 PMCID: PMC9611122 DOI: 10.3390/ma15207315] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 09/29/2022] [Accepted: 09/30/2022] [Indexed: 06/12/2023]
Abstract
Energy self-sufficiency, as well as optimal management of power in buildings is gaining importance, while obtaining power from traditional fossil energy sources is becoming more and more expensive. In this context, millimeter-scale metasurfaces can be employed to harvest energy from microwave sources. They can also be used as sensors in the microwave regime for efficient power management solutions. In the current study, a simple spray printing method is proposed to develop metasurfaces in construction materials, i.e., plasterboard and wood. Such materials are used in the interior design of buildings; therefore, the implementation of metasurfaces in large areas, such as walls, doors and floors, is realized. The fabricated metasurfaces were characterized regarding their electromagnetic performance. It is hereby shown that the investigated metasurfaces exhibit an efficient electromagnetic response in the frequency range (4-7 GHz), depending on the MS. Thus, spray-printed metasurfaces integrated on construction materials can potentially be used for electromagnetic applications, for buildings' power self-efficiency and management.
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Affiliation(s)
- Zacharias Viskadourakis
- Institute of Electronic Structure and Laser (IESL), Foundation for Research and Technology—Hellas (FORTH), N. Plastira 100, Vassilika Vouton, 70013 Heraklion, Greece
| | - Konstantinos Grammatikakis
- Materials Science and Technology Department, University of Crete, Vassilika Vouton, 70013 Heraklion, Greece
| | - Klytaimnistra Katsara
- Institute of Electronic Structure and Laser (IESL), Foundation for Research and Technology—Hellas (FORTH), N. Plastira 100, Vassilika Vouton, 70013 Heraklion, Greece
- Department of Agriculture, Hellenic Mediterranean University—Hellas, Estavromenos, 70013 Heraklion, Greece
| | - Argyri Drymiskianaki
- Materials Science and Technology Department, University of Crete, Vassilika Vouton, 70013 Heraklion, Greece
| | - George Kenanakis
- Institute of Electronic Structure and Laser (IESL), Foundation for Research and Technology—Hellas (FORTH), N. Plastira 100, Vassilika Vouton, 70013 Heraklion, Greece
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5
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Shim H, Monticone F, Miller OD. Fundamental Limits to the Refractive Index of Transparent Optical Materials. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2103946. [PMID: 34510577 DOI: 10.1002/adma.202103946] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 07/26/2021] [Indexed: 06/13/2023]
Abstract
Increasing the refractive index available for optical and nanophotonic systems opens new vistas for design, for applications ranging from broadband metalenses to ultrathin photovoltaics to high-quality-factor resonators. In this work, fundamental limits to the refractive index of any material are derived, given only the underlying electron density and either the maximum allowable dispersion or the minimum bandwidth of interest. In the realm of small to modest dispersion, the bounds are closely approached and not surpassed by a wide range of natural materials, showing that nature has already nearly reached a Pareto frontier for refractive index and dispersion. Conversely, for narrow-bandwidth applications, nature does not provide the highly dispersive, high-index materials that the bounds suggest should be possible. The theory of composites to identify metal-based metamaterials that can exhibit small losses and sizeable increases in refractive index over the current best materials is used. Moreover, if the "elusive lossless metal" can be synthesized, it is shown that it would enable arbitrarily high refractive index in the high-dispersion regime, nearly achieving the bounds even at refractive indices of 100 and beyond at optical frequencies.
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Affiliation(s)
- Hyungki Shim
- Department of Applied Physics and Energy Sciences Institute, Yale University, New Haven, CT, 06511, USA
- Department of Physics, Yale University, New Haven, CT, 06511, USA
| | - Francesco Monticone
- School of Electrical and Computer Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Owen D Miller
- Department of Applied Physics and Energy Sciences Institute, Yale University, New Haven, CT, 06511, USA
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6
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Huh JH, Kim K, Im E, Lee J, Cho Y, Lee S. Exploiting Colloidal Metamaterials for Achieving Unnatural Optical Refractions. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e2001806. [PMID: 33079414 DOI: 10.1002/adma.202001806] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Revised: 04/27/2020] [Indexed: 05/28/2023]
Abstract
The scaling down of meta-atoms or metamolecules (collectively denoted as metaunits) is a long-lasting issue from the time when the concept of metamaterials was first suggested. According to the effective medium theory, which is the foundational concept of metamaterials, the structural sizes of meta-units should be much smaller than the working wavelengths (e.g., << 1/5 wavelength). At relatively low frequency regimes (e.g., microwave and terahertz), the conventional monolithic lithography can readily address the materialization of metamaterials. However, it is still challenging to fabricate optical metamaterials (metamaterials working at optical frequencies such as the visible and near-infrared regimes) through the lithographic approaches. This serves as the rationale for using colloidal self-assembly as a strategy for the realization of optical metamaterials. Colloidal self-assembly can address various critical issues associated with the materialization of optical metamaterials, such as achieving nanogaps over a large area, increasing true 3D structural complexities, and cost-effective processing, which all are difficult to attain through monolithic lithography. Nevertheless, colloidal self-assembly is still a toolset underutilized by optical engineers. Here, the design principle of the colloidally self-assembled optical metamaterials exhibiting unnatural refractions, the practical challenge of relevant experiments, and the future opportunities are critically reviewed.
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Affiliation(s)
- Ji-Hyeok Huh
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul, 02841, Republic of Korea
| | - Kwangjin Kim
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul, 02841, Republic of Korea
| | - Eunji Im
- Department of Biomicrosystem Technology, Korea University, Seoul, 02841, Republic of Korea
| | - Jaewon Lee
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul, 02841, Republic of Korea
| | - YongDeok Cho
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul, 02841, Republic of Korea
| | - Seungwoo Lee
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul, 02841, Republic of Korea
- Department of Biomicrosystem Technology, Korea University, Seoul, 02841, Republic of Korea
- Department of Integrative Energy Engineering (IEE) and KU Photonics Center, Korea University, Seoul, 02841, Republic of Korea
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7
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Vorobyev V, Shchelokova A, Zivkovic I, Slobozhanyuk A, Baena JD, Del Risco JP, Abdeddaim R, Webb A, Glybovski S. An artificial dielectric slab for ultra high-field MRI: Proof of concept. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2020; 320:106835. [PMID: 33065392 DOI: 10.1016/j.jmr.2020.106835] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 09/02/2020] [Accepted: 09/21/2020] [Indexed: 06/11/2023]
Abstract
High-permittivity dielectric pads, i.e., thin, flexible slabs, usually consisting of mixed ceramic powders and liquids, have been previously shown to increase the magnetic field at high and ultra high-fields in regions of low efficiency of transmit coils, thus improving the homogeneity of images. However, their material parameters can change with time, and some materials they contain are bio incompatible. This article presents an alternative approach replacing ceramic mixtures with a low-cost and stable artificial dielectric slab. The latter comprises a stack of capacitive grids realized using multiple printed-circuit boards. Results in this article show that the proposed artificial dielectric structure can obtain the same increase in the local transmit radiofrequency magnetic field distribution in a head phantom at 7 T as the conventional dielectric pad.
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Affiliation(s)
- Vsevolod Vorobyev
- Department of Physics and Engineering, ITMO University, 197101 St. Petersburg, Russia.
| | - Alena Shchelokova
- Department of Physics and Engineering, ITMO University, 197101 St. Petersburg, Russia.
| | - Irena Zivkovic
- Department of Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden 2333 ZA, the Netherlands.
| | - Alexey Slobozhanyuk
- Department of Physics and Engineering, ITMO University, 197101 St. Petersburg, Russia.
| | - Juan D Baena
- Department of Physics, Universidad Nacional de Colombia, Bogota 111321, Colombia.
| | - Juan P Del Risco
- School of Exact Sciences and Engineering, Universidad Sergio Arboleda, Bogota 111711, Colombia.
| | - Redha Abdeddaim
- Aix Marseille University, CNRS, Centrale Marseille, Institut Fresnel, F-13013 Marseille, France.
| | - Andrew Webb
- Department of Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden 2333 ZA, the Netherlands.
| | - Stanislav Glybovski
- Department of Physics and Engineering, ITMO University, 197101 St. Petersburg, Russia.
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8
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Dispersion Analysis of Periodically Loaded Transmission Lines with Twist Symmetry Using the Mode-Matching Technique. APPLIED SCIENCES-BASEL 2020. [DOI: 10.3390/app10175990] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A mode-matching formulation is presented and used to analyze the dispersion properties of twist-symmetric transmission lines. The structures are coaxial lines periodically loaded with infinitely thin screens, which are rotated with respect to each other to possess twist symmetry. The results obtained using the proposed formulation are in good agreement with those of commercial simulators. Furthermore, using the presented mode-matching formulation, it is demonstrated that the propagation characteristics in the twist-symmetric structures are linked to the scattering and coupling of the higher order modes. The physical insight offered by this analysis is valuable for the design of various electromagnetic devices, such as filters, antennas, and phase-shifters.
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9
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Huh JH, Lee J, Lee S. Soft Plasmonic Assemblies Exhibiting Unnaturally High Refractive Index. NANO LETTERS 2020; 20:4768-4774. [PMID: 32239953 DOI: 10.1021/acs.nanolett.0c00422] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The increases in refractive indices (n) of materials are crucial for transformative optical technologies. With the progress of monolithic lithography, large advances have been achieved with several semiconductors, including silicon, germanium, and gallium arsenide, which generally provide higher n of ∼4.0 compared to those of other elements. Nevertheless, above this upper limit of naturally available n, the range of light-matter interactions could be unprecedentedly expanded, which in turn enriches the possible applications. Here, we present a soft self-assembly of polyhedral Au colloids as a promising method to achieve unnaturally high n values. The interfacial assembly of Au nanocubes provides n of 6.4 at the resonant wavelength (near-infrared) and 4.5 in the off-resonant regimes (mid-infrared), which have not been previously reached. The soft self-assembly of polyhedral Au colloids can be a versatile and highly effective route for the fabrication of optical metamaterials with unnaturally high n values.
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Affiliation(s)
- Ji-Hyeok Huh
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Republic of Korea
| | - Jaewon Lee
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Republic of Korea
| | - Seungwoo Lee
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Republic of Korea
- Department of Biomicrosystem Technology, Korea University, Seoul 02841, Republic of Korea
- KU Photonics Center, Korea University, Seoul 02841, Republic of Korea
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10
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High Refractive Index Electromagnetic Devices in Printed Technology Based on Glide-Symmetric Periodic Structures. APPLIED SCIENCES-BASEL 2020. [DOI: 10.3390/app10093216] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We demonstrate the beneficial effects of introducing glide symmetry in a two-dimensional periodic structure. Specifically, we investigate dielectric parallel plate waveguides periodically loaded with Jerusalem cross slots in three configurations: conventional, mirror- and glide-symmetric. Out of these three configurations, it is demonstrated that the glide-symmetric structure is the least dispersive and has the most isotropic response. Furthermore, the glide-symmetric structure provides the highest effective refractive index, which enables the realization of a broader range of electromagnetic devices. To illustrate the potential of this glide-symmetric unit cell, a Maxwell fish-eye lens is designed to operate at 5 GHz. The lens is manufactured in printed circuit board technology. Simulations and measurements are in good agreement and a measured peak transmission coefficient of −0.5 dB is achieved.
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11
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Fully Metallic Flat Lens Based on Locally Twist-Symmetric Array of Complementary Split-Ring Resonators. Symmetry (Basel) 2019. [DOI: 10.3390/sym11040581] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
In this article, we demonstrate how twist symmetries can be employed in the design of flat lenses. A lens design is proposed, consisting of 13 perforated metallic sheets separated by an air gap. The perforation in the metal is a two-dimensional array of complementary split-ring resonators. In this specific design, the twist symmetry is local, as it is only applied to the unit cell of the array. Moreover, the twist symmetry is an approximation, as it is only applied to part of the unit cell. First, we demonstrate that, by varying the order of twist symmetry, the phase delay experienced by a wave propagating through the array can be accurately controlled. Secondly, a lens is designed by tailoring the unit cells throughout the aperture of the lens in order to obtain the desired phase delay. Simulation and measurement results demonstrate that the lens successfully transforms a spherical wave emanating from the focal point into a plane wave at the opposite side of the lens. The demonstrated concepts find application in future wireless communication networks where fully-metallic directive antennas are desired.
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12
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One-Plane Glide-Symmetric Holey Structures for Stop-Band and Refraction Index Reconfiguration. Symmetry (Basel) 2019. [DOI: 10.3390/sym11040495] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
This work presents a new configuration to create glide-symmetric structures in a single plane, which facilitates fabrication and avoids alignment problems in the assembly process compared to traditional glide-symmetric structures based on several planes. The proposed structures can be printed on the metal face of a dielectric substrate, which acts as a support. The article includes a parametric study based on dispersion diagrams on the appearance of stop-bands and phase-shifting by breaking the symmetry. In addition, a procedure to regenerate symmetry is proposed that may be useful for reconfigurable devices. Finally, the measured and simulated S parameters of 10 × 10 unit-cell structures are presented to illustrate the attenuation in these stop-bands and the refractive index of the propagation modes. The attenuation obtained is greater than 30 dB in the stop-band for the symmetry-broken prototype.
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13
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Kolle M, Lee S. Progress and Opportunities in Soft Photonics and Biologically Inspired Optics. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2018; 30:1702669. [PMID: 29057519 DOI: 10.1002/adma.201702669] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Revised: 06/13/2017] [Indexed: 05/24/2023]
Abstract
Optical components made fully or partially from reconfigurable, stimuli-responsive, soft solids or fluids-collectively referred to as soft photonics-are poised to form the platform for tunable optical devices with unprecedented functionality and performance characteristics. Currently, however, soft solid and fluid material systems still represent an underutilized class of materials in the optical engineers' toolbox. This is in part due to challenges in fabrication, integration, and structural control on the nano- and microscale associated with the application of soft components in optics. These challenges might be addressed with the help of a resourceful ally: nature. Organisms from many different phyla have evolved an impressive arsenal of light manipulation strategies that rely on the ability to generate and dynamically reconfigure hierarchically structured, complex optical material designs, often involving soft or fluid components. A comprehensive understanding of design concepts, structure formation principles, material integration, and control mechanisms employed in biological photonic systems will allow this study to challenge current paradigms in optical technology. This review provides an overview of recent developments in the fields of soft photonics and biologically inspired optics, emphasizes the ties between the two fields, and outlines future opportunities that result from advancements in soft and bioinspired photonics.
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Affiliation(s)
- Mathias Kolle
- Department of Mechanical Engineering, Massachusetts Institute of Technology (MIT), Cambridge, MA, 02139, USA
| | - Seungwoo Lee
- SKKU Advanced Institute of Nanotechnology (SAINT), Department of Nano Engineering and School of Chemical Engineering, Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea
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