1
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Zhang Y, Fan H, Zhang Y, Ran L, Ye D, Chen X. Fourier metasurface cloaking: unidirectional cloaking of electrically large cylinder under oblique incidence. OPTICS EXPRESS 2024; 32:1047-1062. [PMID: 38175120 DOI: 10.1364/oe.507109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Accepted: 12/10/2023] [Indexed: 01/05/2024]
Abstract
The existence of a non-electrically-small scatterer adjacent to the source can severely distort the radiation and lead to a poor electromagnetic compatibility. In this work, we use a conducting hollow cylinder to shield a cylindrical scatterer. The cylinder is shelled with a single dielectric layer enclosed by an electromagnetic metasurface. The relationship between the scattering field and the surface impedance is derived analytically. By optimizing the Fourier expansion coefficients of the surface impedance distribution along ϕ-dimension, the scattering cross-section can be effectively reduced. This unidirectional cloaking method is valid for both TM/TE and non-TM/TE incident field and is not limited to a plane-wave incident field. The accuracy and effectiveness of the method are verified by four cloaking scenarios in microwave regime. We demonstrate that with the surface impedance obtained by the proposed method, a metasurface is designed with physical subwavelength structures. We also show a cloaking scenario under a magnetic dipole radiation, which is closer to the case of a realistic antenna. This method can be further applied to cloaking tasks in terahertz and optical regimes.
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2
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Osanloo N, Ahmadi V, Naser-Moghaddasi M, Darabi E. Analytical study of gold-DNA nano core-shell cloaking characteristics for drug delivery and cancer therapy. RSC Adv 2023; 13:23244-23253. [PMID: 37533786 PMCID: PMC10392965 DOI: 10.1039/d3ra03338d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Accepted: 07/17/2023] [Indexed: 08/04/2023] Open
Abstract
The cloaking characteristics of biocells can be considered as a factor to determine drug absorption by the tissues. The metal-organic core-shell structure can act as a cloak around the molecules of tissue and can be used as a nanomachine for drug delivery. Thus, we define a ratio of drug absorption based on frequency red-shift and the effective permittivity in the optical spectrum. Here, a cylinder of molecules coated by plasmonic nano core-shells is proposed for measuring the cloaking characteristics of biocells. The overall bandwidth of the proposed cloak for reflectance less than -10 dB is 36%. We check the effect of the filling factors of nanoparticles on the reflection and the frequency response of the tissue. Besides the frequency red-shift and change in the level of reflection, the phase and impedance are extracted. We could obtain the normalized scattering cross-section of 5 dB lower than the cylinder without cloak for the cylinder with a gold-DNA core-shell cloak. Here, we modify the Maxwell-Garnett equation for a cylindrical structure to obtain the effective value of the permittivity for cancer and normal tissues. The results show that obtained permittivity from the simulation has a good match with the calculated permittivity from the Maxwell-Garnet equation. Therefore, this approach can be considered as an efficient method for drug absorption and diagnosis of cancer cells from normal cells.
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Affiliation(s)
- Nahid Osanloo
- Faculty of Engineering, Science and Research Branch, Islamic Azad University Tehran Iran
| | - Vahid Ahmadi
- Department of Electrical and Computer Engineering, Tarbiat Modares University Tehran Iran
| | | | - Elham Darabi
- Plasma Physics Research Center, Science and Research Branch, Islamic Azad University Tehran Iran
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3
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Mystilidis C, Zheng X, Xomalis A, Vandenbosch GAE. A Potential‐Based Boundary Element Implementation for Modeling Multiple Scattering from Local and Nonlocal Plasmonic Nanowires. ADVANCED THEORY AND SIMULATIONS 2023. [DOI: 10.1002/adts.202200722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Christos Mystilidis
- WaveCore Division Department of Electrical Engineering, KU Leuven Kasteelpark Arenberg 10, BUS 2444 Leuven B‐3001 Belgium
| | - Xuezhi Zheng
- WaveCore Division Department of Electrical Engineering, KU Leuven Kasteelpark Arenberg 10, BUS 2444 Leuven B‐3001 Belgium
| | - Angelos Xomalis
- Empa Swiss Federal Laboratories for Material Science and Technology Laboratory for Mechanics of Materials and Nanostructures Feuerwerkerstrasse 39 Thun 3602 Switzerland
| | - Guy A. E. Vandenbosch
- WaveCore Division Department of Electrical Engineering, KU Leuven Kasteelpark Arenberg 10, BUS 2444 Leuven B‐3001 Belgium
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4
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Ma ZR, Huang XC, Li TJ, Wang HC, Liu GC, Wang ZS, Li B, Li WB, Zhu LF. First Observation of New Flat Line Fano Profile via an X-Ray Planar Cavity. PHYSICAL REVIEW LETTERS 2022; 129:213602. [PMID: 36461956 DOI: 10.1103/physrevlett.129.213602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 11/10/2021] [Accepted: 09/27/2022] [Indexed: 06/17/2023]
Abstract
A new Fano profile of a flat line is achieved experimentally by manipulating the relative amplitude of the continuum path, when q takes the pure imaginary number of -i in the x-ray regime. The underlying mechanism is that the interference term in the scattering will cancel the discrete term exactly. This new Fano profile renders only an observable continuum along with an invisible response to the discrete state of atomic resonance. The results suggest not only a different strategy to invisibility studies which provides a possible tool to identify weaker structures hidden by the strong white line, but also a new scenario to enrich the manipulations of two-path interference and nonlinear Fano resonance.
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Affiliation(s)
- Zi-Ru Ma
- Hefei National Research Center for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Xin-Chao Huang
- Hefei National Research Center for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Tian-Jun Li
- Hefei National Research Center for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Hong-Chang Wang
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire, OX11 0DE, United Kingdom
| | - Gen-Chang Liu
- MOE Key Laboratory of Advanced Micro-Structured Materials, Institute of Precision Optical Engineering (IPOE), School of Physics science and Engineering, Tongji University, Shanghai 200092, People's Republic of China
| | - Zhan-Shan Wang
- MOE Key Laboratory of Advanced Micro-Structured Materials, Institute of Precision Optical Engineering (IPOE), School of Physics science and Engineering, Tongji University, Shanghai 200092, People's Republic of China
| | - Bo Li
- Hefei National Research Center for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Wen-Bin Li
- MOE Key Laboratory of Advanced Micro-Structured Materials, Institute of Precision Optical Engineering (IPOE), School of Physics science and Engineering, Tongji University, Shanghai 200092, People's Republic of China
| | - Lin-Fan Zhu
- Hefei National Research Center for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
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5
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Metasurfaces for Far-Field Radiation Pattern Correction of Antennas under Dielectric Seamed-Radomes. MATERIALS 2022; 15:ma15020665. [PMID: 35057381 PMCID: PMC8780555 DOI: 10.3390/ma15020665] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 01/13/2022] [Accepted: 01/14/2022] [Indexed: 11/17/2022]
Abstract
A high-index dielectric radome seam is camouflaged with respect to a low-index dielectric radome panel by tuning the seam with carefully engineered metasurfaces. A transmission-line approach is used to model the metasurface-tuned seam and analytically retrieve the corresponding surface impedance, from which the unit-cell design is then tailored. Full-wave simulations and microwave antenna measurements performed on a proof-of-concept prototype validate the undesired scattering suppression effect in the case of normally and obliquely incident transverse electric and transverse magnetic wave illuminations. Robustness of the proposed solution to fabrication tolerances is also reported. The study presents metasurface-tuning as an easily implementable, frequency adjustable, and polarization insensitive solution to reduce the scattering of dielectric mechanical seams and improve the overall transparency performance of radome structures.
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6
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Sadrara M, Miri M. Collective cloaking of a cluster of electrostatically defined core-shell quantum dots in graphene. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2022; 34:115703. [PMID: 34920446 DOI: 10.1088/1361-648x/ac4440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 12/17/2021] [Indexed: 06/14/2023]
Abstract
We study cloaking of aclusterof electrostatically defined core-shell quantum dots in graphene. Guided by the generalized multiparticle Mie theory, the Dirac electron scattering from a cluster of quantum dots is addressed. Indeed distant quantum dots may experience a sort of individual cloaking. But despite the multiple scattering of an incident electron from a set of adjacent quantum dots,collective cloakingmay happen. Via a proper choice of the radii and bias voltages of shells, two most important scattering coefficients and hence the scattering efficiency of the cluster dramatically decrease. Energy-selective electron cloaks are realizable. More importantly, clusters simultaneously transparent to electrons of different energies, are achievable. Being quite sensitive to applied bias voltages, clusters of core-shell quantum dots may be used to develop switches with high on-off ratios.
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Affiliation(s)
- Mahdiyeh Sadrara
- School of Nano Science, Institute for Research in Fundamental Sciences (IPM), PO Box 19395-5531, Tehran, Iran
| | - MirFaez Miri
- Department of Physics, University of Tehran, PO Box 14395-547, Tehran, Iran
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7
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Xu L, Chen H. Transformation Metamaterials. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2005489. [PMID: 34622508 DOI: 10.1002/adma.202005489] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 05/01/2021] [Indexed: 06/13/2023]
Abstract
Based on the form-invariance of Maxwell's equations under coordinate transformations, mathematically smooth deformation of space can be physically equivalent to inhomogeneous and anisotropic electromagnetic (EM) medium (called a transformation medium). It provides a geometric recipe to control EM waves at will. A series of examples of achieving transformation media by artificially structured units from conventional materials is summarized here. Such concepts are firstly implemented for EM waves, and then extended to other wave dynamics, such as elastic waves, acoustic waves, surface water waves, and even stationary fields. These shall be cataloged as transformation metamaterials. In addition, it might be conceptually attractive and practically useful to control diverse waves for multi-physics designs.
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Affiliation(s)
- Lin Xu
- Department of Physics and Institute of Electromagnetics and Acoustics, Xiamen University, Xiamen, 361005, China
- Information Materials and Intelligent Sensing Laboratory of Anhui Province & Institutes of Physical Science and Information Technology, Anhui University, Hefei, 230601, China
| | - Huanyang Chen
- Department of Physics and Institute of Electromagnetics and Acoustics, Xiamen University, Xiamen, 361005, China
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8
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Equivalence between positive and negative refractive index materials in electrostatic cloaks. Sci Rep 2021; 11:20467. [PMID: 34650100 PMCID: PMC8516860 DOI: 10.1038/s41598-021-00124-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 10/07/2021] [Indexed: 11/08/2022] Open
Abstract
We investigate, both theoretically and numerically, the equivalence relationship between the positive and negative refraction index dielectric materials in electrostatic invisibility cloak. We have derived an analytical formula that enables fast calculate the corresponding positive dielectric constant from the negative refraction index material. The numerical results show that the negative refraction index material can be replaced by the positive refractive index materials in the static field cloak. This offers some new viewpoints for designing new sensing systems and devices in physics, colloid science, and engineering applications.
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9
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Yang P, Wang X, Schiavone P. Elastic cloaking for a periodic distribution of parallel finite cracks. Proc Math Phys Eng Sci 2021. [DOI: 10.1098/rspa.2020.0997] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We achieve elastic cloaking for a periodic distribution of an infinite number of parallel finite mode III cracks by means of the complex variable method and the theory of Cauchy singular integral equations. The cloaking bimaterial structure is composed of an undisturbed uniformly stressed left half-plane perfectly bonded via a wavy interface to the right half-plane which contains periodic cracks. The original design of the wavy interface and the positions of the periodic cracks are ultimately reduced to the solution of a Cauchy singular integral equation which can be solved numerically.
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Affiliation(s)
- Ping Yang
- School of Mechanical and Power Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, People's Republic of China
| | - Xu Wang
- School of Mechanical and Power Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, People's Republic of China
| | - Peter Schiavone
- Department of Mechanical Engineering, University of Alberta, 10–203 Donadeo Innovation Centre for Engineering, Edmonton, Alberta, Canada T6G 1H9
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10
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Chen C, Huang Y, Wu K, Bifano TG, Anderson SW, Zhao X, Zhang X. Polarization insensitive, metamaterial absorber-enhanced long-wave infrared detector. OPTICS EXPRESS 2020; 28:28843-28857. [PMID: 33114794 DOI: 10.1364/oe.403105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Accepted: 08/27/2020] [Indexed: 06/11/2023]
Abstract
Detecting low energy photons, such as photons in the long-wave infrared range, is a technically challenging proposition using naturally occurring materials. In order to address this challenge, we herein demonstrate a micro-bolometer featuring an integrated metamaterial absorber (MA), which takes advantage of the resonant absorption and frequency selective properties of the MA. Importantly, our micro-bolometer exhibits polarization insensitivity and high absorption due to a novel metal-insulator-metal (MIM) absorber design, operating at 8-12 µm wavelength. The metamaterial structures we report herein feature an interconnected design, optimized towards their application to micro-bolometer-based, long-wave infrared detection. The micro-bolometers were fabricated using a combination of conventional photolithography and electron beam lithography (EBL), the latter owing to the small feature sizes within the design. The absorption response was designed using the coupled mode theory (CMT) and the finite integration technique, with the fabricated devices characterized using Fourier-transform infrared spectroscopy (FTIR). The metamaterial-based micro-bolometer exhibits a responsivity of approximately 198 V/W over the 8-12 µm wavelength regime, detectivity of ∼ 0.6 × 109 Jones, thermal response time of ∼ 3.3 ms, and a noise equivalent temperature difference (NETD) of ∼33 mK under 1mA biasing current at room-temperature and atmosphere pressure. The ultimate detectivity and NETD are limited by Johnson noise and heat loss with thermal convection through air; however, further optimization could be achieved by reducing the thermal conductivity via vacuum packaging. Under vacuum conditions, the detectivity may be increased in excess of two-fold, to ∼ 1.5 × 109 Jones. Finally, an infrared image of a soldering iron was generated using a single-pixel imaging process, serving as proof-of-concept of this detection platform. The results presented in this work pave the road towards high-efficiency and frequency-selective detection in the long-wave infrared range through the integration of infrared MAs with micro-bolometers.
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11
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Khan MI, Ghosh S, Baxter R, Kim AD. Modeling broadband cloaking using 3D nano-assembled plasmonic meta-structures. OPTICS EXPRESS 2020; 28:22732-22747. [PMID: 32752530 DOI: 10.1364/oe.395840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 06/03/2020] [Indexed: 06/11/2023]
Abstract
The concept of "cloaking" an object is a very attractive one, especially in the visible (VIS) and near infra-red (NIR) regions of the electromagnetic spectrum, as that would reduce the visibility of an object to the eye. One possible route to achieving this goal is by leveraging the plasmonic property of metallic nanoparticles (NPs). We model and simulate light in the VIS and NIR scattered by a core of a homogeneous medium, covered by plasmonic cloak that is a spherical shell composed of gold nanoparticles (AuNPs). To consider realistic, scalable, and robust plasmonic cloaks that are comparable, or larger, in size to the wavelength, we introduce a multiscale simulation platform. This model uses the multiple scattering theory of Foldy and Lax to model interactions of light with AuNPs combined with the method of fundamental solutions to model interactions with the core. Numerical results of our simulations for the scattering cross-sections of core-shell composite indicate significant scattering suppression of up to 50% over a substantial portion of the desired spectral range (400 - 600 nm) for cores as large as 900 nm in diameter by a suitable combination of AuNP sizes and filling fractions of AuNPs in the shell.
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12
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Zhang YJ, Li P, Galdi V, Tong MS, Alù A. Manipulating the scattering pattern with non-Hermitian particle arrays. OPTICS EXPRESS 2020; 28:19492-19507. [PMID: 32672225 DOI: 10.1364/oe.395942] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Accepted: 06/04/2020] [Indexed: 06/11/2023]
Abstract
We show that an array of non-Hermitian particles can enable advanced manipulations of the scattering pattern, beyond what is possible with passive structures. Active linear elements are shown to provide zero forward scattering without sacrificing the total scattered power, and by adding more particles, it is possible to control the zero-scattering direction at will. We apply our theory to realistic implementations of scatterer arrays, using loaded dipole antennas in which we tune the load impedance and investigate the stability of these arrays based on a realistic dispersion model for the gain elements. Finally, we discuss the possibility of controlling multiple frequencies to enable broadband control of the scattering pattern.
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13
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Abstract
One of the most exciting applications of metaparticles and metasurfaces consists in the magnetic light excitation. However, the principal limitation is due to parasitic extra multipoles of electric family excited in magnetic dipole meta-particles characterized by a radiating nature and corresponding radiating losses. In this paper, we propose the “ideal magnetic dipole” with suppressed additional multipoles except of magnetic dipole moment in the scattered field from a cylindrical object by using mantle cloaking based on metasurface and on anapole concept. The considered metasurface consists of a periodic width modulated microstrip line, with a sinusoidally shaped profile unit cell printed on a dielectric substrate.
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14
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Ha M, Kim JH, You M, Li Q, Fan C, Nam JM. Multicomponent Plasmonic Nanoparticles: From Heterostructured Nanoparticles to Colloidal Composite Nanostructures. Chem Rev 2019; 119:12208-12278. [PMID: 31794202 DOI: 10.1021/acs.chemrev.9b00234] [Citation(s) in RCA: 178] [Impact Index Per Article: 35.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Plasmonic nanostructures possessing unique and versatile optoelectronic properties have been vastly investigated over the past decade. However, the full potential of plasmonic nanostructure has not yet been fully exploited, particularly with single-component homogeneous structures with monotonic properties, and the addition of new components for making multicomponent nanoparticles may lead to new-yet-unexpected or improved properties. Here we define the term "multi-component nanoparticles" as hybrid structures composed of two or more condensed nanoscale domains with distinctive material compositions, shapes, or sizes. We reviewed and discussed the designing principles and synthetic strategies to efficiently combine multiple components to form hybrid nanoparticles with a new or improved plasmonic functionality. In particular, it has been quite challenging to precisely synthesize widely diverse multicomponent plasmonic structures, limiting realization of the full potential of plasmonic heterostructures. To address this challenge, several synthetic approaches have been reported to form a variety of different multicomponent plasmonic nanoparticles, mainly based on heterogeneous nucleation, atomic replacements, adsorption on supports, and biomolecule-mediated assemblies. In addition, the unique and synergistic features of multicomponent plasmonic nanoparticles, such as combination of pristine material properties, finely tuned plasmon resonance and coupling, enhanced light-matter interactions, geometry-induced polarization, and plasmon-induced energy and charge transfer across the heterointerface, were reported. In this review, we comprehensively summarize the latest advances on state-of-art synthetic strategies, unique properties, and promising applications of multicomponent plasmonic nanoparticles. These plasmonic nanoparticles including heterostructured nanoparticles and composite nanostructures are prepared by direct synthesis and physical force- or biomolecule-mediated assembly, which hold tremendous potential for plasmon-mediated energy transfer, magnetic plasmonics, metamolecules, and nanobiotechnology.
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Affiliation(s)
- Minji Ha
- Department of Chemistry , Seoul National University , Seoul 08826 , South Korea
| | - Jae-Ho Kim
- Department of Chemistry , Seoul National University , Seoul 08826 , South Korea
| | - Myunghwa You
- Department of Chemistry , Seoul National University , Seoul 08826 , South Korea
| | - Qian Li
- School of Chemistry and Chemical Engineering, and Institute of Molecular Medicine, Renji Hospital, School of Medicine , Shanghai Jiao Tong University , Shanghai 200240 , China
| | - Chunhai Fan
- School of Chemistry and Chemical Engineering, and Institute of Molecular Medicine, Renji Hospital, School of Medicine , Shanghai Jiao Tong University , Shanghai 200240 , China
| | - Jwa-Min Nam
- Department of Chemistry , Seoul National University , Seoul 08826 , South Korea
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15
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Tasolamprou AC, Koulouklidis AD, Daskalaki C, Mavidis CP, Kenanakis G, Deligeorgis G, Viskadourakis Z, Kuzhir P, Tzortzakis S, Kafesaki M, Economou EN, Soukoulis CM. Experimental Demonstration of Ultrafast THz Modulation in a Graphene-Based Thin Film Absorber through Negative Photoinduced Conductivity. ACS PHOTONICS 2019; 6:720-727. [PMID: 30918912 PMCID: PMC6429433 DOI: 10.1021/acsphotonics.8b01595] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Indexed: 05/03/2023]
Abstract
We present an experimental demonstration and interpretation of an ultrafast optically tunable, graphene-based thin film absorption modulator for operation in the THz regime. The graphene-based component consists of a uniform CVD-grown graphene sheet stacked on an SU-8 dielectric substrate that is grounded by a metallic ground plate. The structure shows enhanced absorption originating from constructive interference of the impinging and reflected waves at the absorbing graphene sheet. The modulation of this absorption, which is demonstrated via a THz time-domain spectroscopy setup, is achieved by applying an optical pump signal, which modifies the conductivity of the graphene sheet. We report an ultrafast (on the order of few ps) absorption modulation on the order of 40% upon photoexcitation. Our results provide evidence that the optical pump excitation results in the degradation of the graphene THz conductivity, which is connected with the generation of hot carriers, the increase of the electronic temperature, and the dominant increase of the scattering rate over the carrier concentration as found in highly doped samples.
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Affiliation(s)
- Anna C. Tasolamprou
- Institute
of Electronic Structure and Laser, FORTH, 70013 Heraklion, Crete, Greece
- E-mail:
| | | | - Christina Daskalaki
- Institute
of Electronic Structure and Laser, FORTH, 70013 Heraklion, Crete, Greece
| | - Charalampos P. Mavidis
- Institute
of Electronic Structure and Laser, FORTH, 70013 Heraklion, Crete, Greece
- Department
of Materials Science and Technology, University
of Crete, 70013 Heraklion, Crete, Greece
| | - George Kenanakis
- Institute
of Electronic Structure and Laser, FORTH, 70013 Heraklion, Crete, Greece
| | - George Deligeorgis
- Institute
of Electronic Structure and Laser, FORTH, 70013 Heraklion, Crete, Greece
| | | | - Polina Kuzhir
- Institute
for Nuclear Problems, Belarusian State University, Bobruiskaya 11, 220030 Minsk, Belarus
- Tomsk
State University, 36
Lenin Avenue, Tomsk 634050, Russia
| | - Stelios Tzortzakis
- Institute
of Electronic Structure and Laser, FORTH, 70013 Heraklion, Crete, Greece
- Department
of Materials Science and Technology, University
of Crete, 70013 Heraklion, Crete, Greece
- Science
Program, Texas A&M University at Qatar, P.O. Box 23874, Doha, Qatar
| | - Maria Kafesaki
- Institute
of Electronic Structure and Laser, FORTH, 70013 Heraklion, Crete, Greece
- Department
of Materials Science and Technology, University
of Crete, 70013 Heraklion, Crete, Greece
| | - Eleftherios N. Economou
- Institute
of Electronic Structure and Laser, FORTH, 70013 Heraklion, Crete, Greece
- Department
of Physics, University of Crete, 70013 Heraklion, Crete, Greece
| | - Costas M. Soukoulis
- Institute
of Electronic Structure and Laser, FORTH, 70013 Heraklion, Crete, Greece
- Ames Laboratory
and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, United States
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16
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Yao K, Unni R, Zheng Y. Intelligent nanophotonics: merging photonics and artificial intelligence at the nanoscale. NANOPHOTONICS 2019; 8:339-366. [PMID: 34290952 PMCID: PMC8291385 DOI: 10.1515/nanoph-2018-0183] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Nanophotonics has been an active research field over the past two decades, triggered by the rising interests in exploring new physics and technologies with light at the nanoscale. As the demands of performance and integration level keep increasing, the design and optimization of nanophotonic devices become computationally expensive and time-inefficient. Advanced computational methods and artificial intelligence, especially its subfield of machine learning, have led to revolutionary development in many applications, such as web searches, computer vision, and speech/image recognition. The complex models and algorithms help to exploit the enormous parameter space in a highly efficient way. In this review, we summarize the recent advances on the emerging field where nanophotonics and machine learning blend. We provide an overview of different computational methods, with the focus on deep learning, for the nanophotonic inverse design. The implementation of deep neural networks with photonic platforms is also discussed. This review aims at sketching an illustration of the nanophotonic design with machine learning and giving a perspective on the future tasks.
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Affiliation(s)
- Kan Yao
- Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX 78712, USA
- Texas Materials Institute, The University of Texas at Austin, Austin, TX 78712, USA
| | - Rohit Unni
- Texas Materials Institute, The University of Texas at Austin, Austin, TX 78712, USA
| | - Yuebing Zheng
- Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX 78712, USA
- Texas Materials Institute, The University of Texas at Austin, Austin, TX 78712, USA
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17
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Shlivinski A, Hadad Y. Beyond the Bode-Fano Bound: Wideband Impedance Matching for Short Pulses Using Temporal Switching of Transmission-Line Parameters. PHYSICAL REVIEW LETTERS 2018; 121:204301. [PMID: 30500223 DOI: 10.1103/physrevlett.121.204301] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Indexed: 06/09/2023]
Abstract
Impedance matching is one of the most important practices in wave engineering as it enables one to maximize the power transfer from the signal source to the load in the wave system. Unfortunately, it is bounded by the Bode-Fano criterion which states that, for any passive, linear, and time-invariant matching network, there is a stringent trade-off between the matching bandwidth and efficiency, implying severe constraints on various electromagnetic and acoustic wave systems. Here, we propose a matching paradigm that overcomes this issue by using a temporal switching of the parameters of a metamaterial-based transmission line, thus revoking the time-invariance assumption underlying the Bode-Fano criterion. Using this scheme we show theoretically that an efficient wideband matching, beyond the Bode-Fano bound, can be achieved for short-time pulses in challenging cases of very high contrast between the load and the generator impedances, and with significant load dispersion, situations common in, e.g., small antenna matching, cloaking, and with applications for ultrawideband communication, high resolution imaging, and more.
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Affiliation(s)
- Amir Shlivinski
- Department of Electrical and Computer Engineering, Ben-Gurion University of the Negev, Beer Sheva, 84105, Israel
| | - Yakir Hadad
- School of Electrical Engineering, Tel-Aviv University, Ramat-Aviv, Tel-Aviv, 69978, Israel
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18
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Mantle Cloaks Based on the Frequency Selective Metasurfaces Designed by Bayesian Optimization. Sci Rep 2018; 8:14033. [PMID: 30232342 PMCID: PMC6145948 DOI: 10.1038/s41598-018-32167-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 09/03/2018] [Indexed: 11/28/2022] Open
Abstract
We propose a full optimization procedure for designing mantle cloaks enclosing arbitrary objects, using sub-wavelength conformal frequency selective surface (FSS). Rely on the scattering cancellation principle of mantle cloak characterized by an average surface reactance, a personal computer can achieve this design procedure. By combing a Bayesian optimization (BO) with an electromagnetic solver, we can automatically find the optimal parameters of a conformal mantle cloak which can nearly cancel the scattering from the enclosed objects. It is shown that the results obtained by our method coincide with those from a rigorous analytical model and the numerical results by full parametric scanning. The proposed methodology opens up a new route for realizing ultra-wideband illusion scattering of electromagnetic wave, which is important for stealth and microwave applications.
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19
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Tunable invisibility cloaking by using isolated graphene-coated nanowires and dimers. Sci Rep 2017; 7:12186. [PMID: 28939888 PMCID: PMC5610338 DOI: 10.1038/s41598-017-12413-4] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 09/07/2017] [Indexed: 11/20/2022] Open
Abstract
We investigate, both theoretically and numerically, a graphene-coated nano-cylinder illuminated by a plane electromagnetic wave in the far-infrared range of frequencies. We have derived an analytical formula that enables fast evaluation of the spectral window with a substantial reduction in scattering efficiency for a sufficiently thin cylinder. This polarization-dependent effect leads to tunable resonant invisibility that can be achieved via modification of graphene chemical potential monitored by the gate voltage. A multi-frequency cloaking mechanism based on dimer coated nanowires is also discussed in detail.
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20
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Luk'yanchuk B, Paniagua-Domínguez R, Kuznetsov AI, Miroshnichenko AE, Kivshar YS. Suppression of scattering for small dielectric particles: anapole mode and invisibility. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2017; 375:rsta.2016.0069. [PMID: 28220000 PMCID: PMC5321830 DOI: 10.1098/rsta.2016.0069] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 09/05/2016] [Indexed: 05/26/2023]
Abstract
We reveal that an isotropic, homogeneous, subwavelength particle with high refractive index can produce ultra-small total scattering. This effect, which follows from the inhibition of the electric dipole radiation, can be identified as a Fano resonance in the scattering efficiency and is associated with the excitation of an anapole mode in the particle. This anapole mode is non-radiative and emerges from the destructive interference of electric and toroidal dipoles. The invisibility effect could be useful for the design of highly transparent optical materials.This article is part of the themed issue 'New horizons for nanophotonics'.
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Affiliation(s)
- Boris Luk'yanchuk
- Data Storage Institute, A*STAR (Agency for Science, Technology and Research), 2 Fusionopolis Way, 08-01 Innovis, 138634, Singapore
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 637371, Singapore
| | - Ramón Paniagua-Domínguez
- Data Storage Institute, A*STAR (Agency for Science, Technology and Research), 2 Fusionopolis Way, 08-01 Innovis, 138634, Singapore
| | - Arseniy I Kuznetsov
- Data Storage Institute, A*STAR (Agency for Science, Technology and Research), 2 Fusionopolis Way, 08-01 Innovis, 138634, Singapore
| | - Andrey E Miroshnichenko
- Nonlinear Physics Centre, Research School of Physics and Engineering, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Yuri S Kivshar
- Nonlinear Physics Centre, Research School of Physics and Engineering, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
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21
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Totero Gongora JS, Favraud G, Fratalocchi A. Fundamental and high-order anapoles in all-dielectric metamaterials via Fano-Feshbach modes competition. NANOTECHNOLOGY 2017; 28:104001. [PMID: 28145277 DOI: 10.1088/1361-6528/aa593d] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
One of the most fascinating possibilities enabled by metamaterials is the strong reduction of the electromagnetic scattering from nanostructures. In dielectric nanoparticles, the formation of a minimal scattering state at specific wavelengths is associated with the excitation of photonic anapoles, which represent a peculiar type of radiationless state and whose existence has been demonstrated experimentally. In this work, we investigate the formation of anapole states in generic dielectric structures by applying a Fano-Feshbach projection scheme, a general technique widely used in the study of quantum mechanical open systems. By expressing the total scattering from the structure in terms of an orthogonal set of internal and external modes, defined in the interior and in the exterior of the dielectric structure, respectively, we show how anapole states are the result of a complex interaction among the resonances of the system and the surrounding environment. We apply our approach to a circular resonator, where we observe the formation of higher-order anapole states, which are originated by the superposition of several internal resonances of the system.
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22
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Wang T, Tang Y, He X, Yan J, Wang C, Feng X. Self-Assembled Raspberry-Like Core/Satellite Nanoparticles for Anti-Inflammatory Protein Delivery. ACS APPLIED MATERIALS & INTERFACES 2017; 9:6902-6907. [PMID: 28155269 DOI: 10.1021/acsami.6b16277] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Functional proteins are very promising for protein therapeutics; however, effective delivery of therapeutic proteins remains challenging. Herein, we developed novel core/satellite nanoparticles by tethering therapeutic proteins to the core/shell polymeric particle surface through cucurbit[8]uril (CB[8])-mediated host-guest interactions. The effectiveness of the core/satellite nanoparticles as protein carrier was demonstrated through the intra-articular delivery of interleukin-1 receptor antagonist (IL-1Ra). We showed that IL-1Ra can effectively self-assemble onto the surface of the polymeric nanoparticles and maintained good protein bioactivity by inhibiting IL-1-mediated signaling. More importantly, in vivo results revealed that IL-1Ra-bounded core/satellite nanoparticles could significantly increase the retention time of IL-1Ra in the rat stifle joint compared to soluble IL-1Ra, which could greatly improve the efficacy of IL-1Ra. These results indicate that the facile host-guest self-assembly can be exploited as an effective approach for realizing the therapeutic potential of proteins.
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Affiliation(s)
- Tingting Wang
- Innovative Drug Research Centre and School of Pharmaceutical Sciences, Chongqing University , Chongqing 401331, China
| | - Yaqin Tang
- Innovative Drug Research Centre and School of Pharmaceutical Sciences, Chongqing University , Chongqing 401331, China
| | - Xiao He
- Innovative Drug Research Centre and School of Pharmaceutical Sciences, Chongqing University , Chongqing 401331, China
| | - Ju Yan
- Innovative Drug Research Centre and School of Pharmaceutical Sciences, Chongqing University , Chongqing 401331, China
| | - Chenhui Wang
- Innovative Drug Research Centre and School of Pharmaceutical Sciences, Chongqing University , Chongqing 401331, China
| | - Xuli Feng
- Innovative Drug Research Centre and School of Pharmaceutical Sciences, Chongqing University , Chongqing 401331, China
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23
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Surface Wave Cloak from Graded Refractive Index Nanocomposites. Sci Rep 2016; 6:29363. [PMID: 27416815 PMCID: PMC4945873 DOI: 10.1038/srep29363] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Accepted: 06/17/2016] [Indexed: 02/02/2023] Open
Abstract
Recently, a great deal of interest has been re-emerged on the possibility to manipulate surface waves, in particular, towards the THz and optical regime. Both concepts of Transformation Optics (TO) and metamaterials have been regarded as one of key enablers for such applications in applied electromagnetics. In this paper, we experimentally demonstrate for the first time a dielectric surface wave cloak from engineered gradient index materials to illustrate the possibility of using nanocomposites to control surface wave propagation through advanced additive manufacturing. The device is designed analytically and validated through numerical simulations and measurements, showing good agreement and performance as an effective surface wave cloak. The underlying design approach has much wider applications, which span from microwave to optics for the control of surface plasmon polaritons (SPPs) and radiation of nanoantennas.
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24
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Höller RPM, Dulle M, Thomä S, Mayer M, Steiner AM, Förster S, Fery A, Kuttner C, Chanana M. Protein-Assisted Assembly of Modular 3D Plasmonic Raspberry-like Core/Satellite Nanoclusters: Correlation of Structure and Optical Properties. ACS NANO 2016; 10:5740-50. [PMID: 26982386 PMCID: PMC4928146 DOI: 10.1021/acsnano.5b07533] [Citation(s) in RCA: 86] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
We present a bottom-up assembly route for a large-scale organization of plasmonic nanoparticles (NPs) into three-dimensional (3D) modular assemblies with core/satellite structure. The protein-assisted assembly of small spherical gold or silver NPs with a hydrophilic protein shell (as satellites) onto larger metal NPs (as cores) offers high modularity in sizes and composition at high satellite coverage (close to the jamming limit). The resulting dispersions of metal/metal nanoclusters exhibit high colloidal stability and therefore allow for high concentrations and a precise characterization of the nanocluster architecture in dispersion by small-angle X-ray scattering (SAXS). Strong near-field coupling between the building blocks results in distinct regimes of dominant satellite-to-satellite and core-to-satellite coupling. High robustness against satellite disorder was proved by UV/vis diffuse reflectance (integrating sphere) measurements. Generalized multiparticle Mie theory (GMMT) simulations were employed to describe the electromagnetic coupling within the nanoclusters. The close correlation of structure and optical property allows for the rational design of core/satellite nanoclusters with tailored plasmonics and well-defined near-field enhancement, with perspectives for applications such as surface-enhanced spectroscopies.
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Affiliation(s)
- Roland P. M. Höller
- Physical Chemistry II, University of Bayreuth, 95440 Bayreuth, Germany
- Leibniz-Institut für Polymerforschung
Dresden e.V., Institute of Physical Chemistry
and Polymer Physics, Hohe Straße 6, 01069 Dresden, Germany
| | - Martin Dulle
- Physical Chemistry
I, University of Bayreuth, 95440 Bayreuth, Germany
| | - Sabrina Thomä
- Physical Chemistry II, University of Bayreuth, 95440 Bayreuth, Germany
| | - Martin Mayer
- Leibniz-Institut für Polymerforschung
Dresden e.V., Institute of Physical Chemistry
and Polymer Physics, Hohe Straße 6, 01069 Dresden, Germany
| | - Anja Maria Steiner
- Leibniz-Institut für Polymerforschung
Dresden e.V., Institute of Physical Chemistry
and Polymer Physics, Hohe Straße 6, 01069 Dresden, Germany
| | - Stephan Förster
- Physical Chemistry
I, University of Bayreuth, 95440 Bayreuth, Germany
| | - Andreas Fery
- Physical Chemistry II, University of Bayreuth, 95440 Bayreuth, Germany
- Leibniz-Institut für Polymerforschung
Dresden e.V., Institute of Physical Chemistry
and Polymer Physics, Hohe Straße 6, 01069 Dresden, Germany
- Physical Chemistry of Polymeric Materials, Technische Universität Dresden, Hohe Straße 6, 01069 Dresden, Germany
- Cluster of Excellence Centre for Advancing Electronics
Dresden (cfaed), Technische Universität
Dresden, 01062 Dresden, Germany
| | - Christian Kuttner
- Physical Chemistry II, University of Bayreuth, 95440 Bayreuth, Germany
- Leibniz-Institut für Polymerforschung
Dresden e.V., Institute of Physical Chemistry
and Polymer Physics, Hohe Straße 6, 01069 Dresden, Germany
- Cluster of Excellence Centre for Advancing Electronics
Dresden (cfaed), Technische Universität
Dresden, 01062 Dresden, Germany
- E-mail:
| | - Munish Chanana
- Physical Chemistry II, University of Bayreuth, 95440 Bayreuth, Germany
- Institute of Building Materials, ETH Zürich, 8093 Zürich, Switzerland
- E-mail:
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25
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Pors A, Ding F, Chen Y, Radko IP, Bozhevolnyi SI. Random-phase metasurfaces at optical wavelengths. Sci Rep 2016; 6:28448. [PMID: 27328635 PMCID: PMC4916468 DOI: 10.1038/srep28448] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 06/02/2016] [Indexed: 11/28/2022] Open
Abstract
Random-phase metasurfaces, in which the constituents scatter light with random phases, have the property that an incident plane wave will diffusely scatter, hereby leading to a complex far-field response that is most suitably described by statistical means. In this work, we present and exemplify the statistical description of the far-field response, particularly highlighting how the response for polarised and unpolarised light might be alike or different depending on the correlation of scattering phases for two orthogonal polarisations. By utilizing gap plasmon-based metasurfaces, consisting of an optically thick gold film overlaid by a subwavelength thin glass spacer and an array of gold nanobricks, we design and realize random-phase metasurfaces at a wavelength of 800 nm. Optical characterisation of the fabricated samples convincingly demonstrates the diffuse scattering of reflected light, with statistics obeying the theoretical predictions. We foresee the use of random-phase metasurfaces for camouflage applications and as high-quality reference structures in dark-field microscopy, while the control of the statistics for polarised and unpolarised light might find usage in security applications. Finally, by incorporating a certain correlation between scattering by neighbouring metasurface constituents new types of functionalities can be realised, such as a Lambertian reflector.
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Affiliation(s)
- Anders Pors
- SDU Nano Optics, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Fei Ding
- SDU Nano Optics, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Yiting Chen
- SDU Nano Optics, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Ilya P Radko
- SDU Nano Optics, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark.,Department of Physics, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark
| | - Sergey I Bozhevolnyi
- SDU Nano Optics, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
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26
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Field-programmable beam reconfiguring based on digitally-controlled coding metasurface. Sci Rep 2016; 6:20663. [PMID: 26861110 PMCID: PMC4748258 DOI: 10.1038/srep20663] [Citation(s) in RCA: 150] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 01/11/2016] [Indexed: 02/02/2023] Open
Abstract
Digital phase shifters have been applied in traditional phased array antennas to realize beam steering. However, the phase shifter deals with the phase of the induced current; hence, it has to be in the path of each element of the antenna array, making the phased array antennas very expensive. Metamaterials and/or metasurfaces enable the direct modulation of electromagnetic waves by designing subwavelength structures, which opens a new way to control the beam scanning. Here, we present a direct digital mechanism to control the scattered electromagnetic waves using coding metasurface, in which each unit cell loads a pin diode to produce binary coding states of “1” and “0”. Through data lines, the instant communications are established between the coding metasurface and the internal memory of field-programmable gate arrays (FPGA). Thus, we realize the digital modulation of electromagnetic waves, from which we present the field-programmable reflective antenna with good measurement performance. The proposed mechanism and functional device have great application potential in new-concept radar and communication systems.
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27
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Vitiello A, Moccia M, Papari GP, D'Alterio G, Vitiello R, Galdi V, Andreone A. Waveguide Characterization of S-Band Microwave Mantle Cloaks for Dielectric and Conducting Objects. Sci Rep 2016; 6:19716. [PMID: 26803985 PMCID: PMC4726170 DOI: 10.1038/srep19716] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 12/10/2015] [Indexed: 11/09/2022] Open
Abstract
We present the experimental characterization of mantle cloaks designed so as to minimize the electromagnetic scattering of moderately-sized dielectric and conducting cylinders at S-band microwave frequencies. Our experimental setup is based on a parallel-plate waveguide system, which emulates a two-dimensional plane-wave scattering scenario, and allows the collection of near-field maps as well as more quantitative assessments in terms of global scattering observables (e.g., total scattering width). Our results, in fairly good agreement with full-wave numerical simulations, provide a further illustration of the mantle- cloak mechanism, including its frequency-sensitivity, and confirm its effectiveness both in restoring the near-field impinging wavefront around the scatterer, and in significantly reducing the overall scattering.
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Affiliation(s)
- Antonino Vitiello
- CNR-SPIN and Department of Physics, University of Naples "Federico II", I-80125 Naples, Italy
| | - Massimo Moccia
- Waves Group, Department of Engineering, University of Sannio, I-82100 Benevento, Italy
| | - Gian Paolo Papari
- CNR-SPIN and Department of Physics, University of Naples "Federico II", I-80125 Naples, Italy
| | | | | | - Vincenzo Galdi
- Waves Group, Department of Engineering, University of Sannio, I-82100 Benevento, Italy
| | - Antonello Andreone
- CNR-SPIN and Department of Physics, University of Naples "Federico II", I-80125 Naples, Italy
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28
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Invisible Hyperbolic Metamaterial Nanotube at Visible Frequency. Sci Rep 2015; 5:16027. [PMID: 26522815 PMCID: PMC4629200 DOI: 10.1038/srep16027] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 10/08/2015] [Indexed: 11/08/2022] Open
Abstract
Subwavelength-scale metal and dielectric nanostructures have served as important building blocks for electromagnetic metamaterials, providing unprecedented opportunities for manipulating the optical response of the matter. Recently, hyperbolic metamaterials have been drawing particular interest because of their unusual optical properties and functionalities, such as negative refraction and hyperlensing of light. Here, as a promising application of a hyperbolic metamaterial at visible frequency, we propose an invisible nanotube that consists of metal and dielectric alternating thin layers. The theoretical study of the light scattering of the layered nanotube reveals that almost-zero scattering can be achieved at a specific wavelength when the transverse-electric- or transverse-magnetic-polarized light is incident to the nanotube. In addition, the layered nanotube can be described as a radial-anisotropic hyperbolic metamaterial nanotube. The low scattering occurs when the effective permittivity of the hyperbolic nanotube in the angular direction is near zero, and thus the invisibility of the layered nanotube can be efficiently obtained by analyzing the equivalent hyperbolic nanotube. Our new method to design and tune an invisible nanostructure represents a significant step toward the practical implementation of unique nanophotonic devices such as invisible photodetectors and low-scattering near-field optical microscopes.
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29
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Prat-Camps J, Navau C, Sanchez A. A Magnetic Wormhole. Sci Rep 2015; 5:12488. [PMID: 26292278 PMCID: PMC4542659 DOI: 10.1038/srep12488] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Accepted: 06/30/2015] [Indexed: 11/09/2022] Open
Abstract
Wormholes are fascinating cosmological objects that can connect two distant regions of the universe. Because of their intriguing nature, constructing a wormhole in a lab seems a formidable task. A theoretical proposal by Greenleaf et al. presented a strategy to build a wormhole for electromagnetic waves. Based on metamaterials, it could allow electromagnetic wave propagation between two points in space through an invisible tunnel. However, an actual realization has not been possible until now. Here we construct and experimentally demonstrate a magnetostatic wormhole. Using magnetic metamaterials and metasurfaces, our wormhole transfers the magnetic field from one point in space to another through a path that is magnetically undetectable. We experimentally show that the magnetic field from a source at one end of the wormhole appears at the other end as an isolated magnetic monopolar field, creating the illusion of a magnetic field propagating through a tunnel outside the 3D space. Practical applications of the results can be envisaged, including medical techniques based on magnetism.
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Affiliation(s)
- Jordi Prat-Camps
- Departament de Física, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Catalonia, Spain
| | - Carles Navau
- Departament de Física, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Catalonia, Spain
| | - Alvaro Sanchez
- Departament de Física, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Catalonia, Spain
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30
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Tailoring Plasmonic Enhanced Upconversion in Single NaYF4:Yb(3+)/Er(3+) Nanocrystals. Sci Rep 2015; 5:10196. [PMID: 25976870 PMCID: PMC4432370 DOI: 10.1038/srep10196] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 04/01/2015] [Indexed: 11/09/2022] Open
Abstract
By using silver nanoplatelets with a widely tunable localized surface plasmon resonance (LSPR), and their corresponding local field enhancement, here we show large manipulation of plasmonic enhanced upconversion in NaYF4:Yb(3+)/Er(3+) nanocrystals at the single particle level. In particular, we show that when the plasmonic resonance of silver nanolplatelets is tuned to 656 nm, matching the emission wavelength, an upconversion enhancement factor ~5 is obtained. However, when the plasmonic resonance is tuned to 980 nm, matching the nanocrystal absorption wavelength, we achieve an enhancement factor of ~22 folds. The precise geometric arrangement between fluorescent nanoparticles and silver nanoplatelets allows us to make, for the first time, a comparative analysis between experimental results and numerical simulations, yielding a quantitative agreement at the single particle level. Such a comparison lays the foundations for a rational design of hybrid metal-fluorescent nanocrystals to harness the upconversion enhancement for biosensing and light harvesting applications.
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31
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Rybin MV, Filonov DS, Belov PA, Kivshar YS, Limonov MF. Switching from visibility to invisibility via Fano resonances: theory and experiment. Sci Rep 2015; 5:8774. [PMID: 25739324 PMCID: PMC4350085 DOI: 10.1038/srep08774] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Accepted: 02/03/2015] [Indexed: 11/14/2022] Open
Abstract
Subwavelength structures demonstrate many unusual optical properties which can be employed for engineering of a new generation of functional metadevices, as well as controlled scattering of light and invisibility cloaking. Here we demonstrate that the suppression of light scattering for any direction of observation can be achieved for a uniform dielectric object with high refractive index, in a sharp contrast to the cloaking with multilayered plasmonic structures suggested previously. Our finding is based on the novel physics of cascades of Fano resonances observed in the Mie scattering from a homogeneous dielectric rod. We observe this effect experimentally at microwaves by employing high temperature-dependent dielectric permittivity of a glass cylinder with heated water. Our results open a new avenue in analyzing the optical response of high-index dielectric nanoparticles and the physics of cloaking.
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Affiliation(s)
- Mikhail V Rybin
- 1] Ioffe Physical-Technical Institute, St. Petersburg 194021, Russia [2] University ITMO, St. Petersburg 197101, Russia
| | | | | | - Yuri S Kivshar
- 1] University ITMO, St. Petersburg 197101, Russia [2] Nonlinear Physics Center, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200, Australia
| | - Mikhail F Limonov
- 1] Ioffe Physical-Technical Institute, St. Petersburg 194021, Russia [2] University ITMO, St. Petersburg 197101, Russia
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32
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Giant nonlinear response from plasmonic metasurfaces coupled to intersubband transitions. Nature 2014; 511:65-9. [PMID: 24990746 DOI: 10.1038/nature13455] [Citation(s) in RCA: 171] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Accepted: 05/09/2014] [Indexed: 11/08/2022]
Abstract
Intersubband transitions in n-doped multi-quantum-well semiconductor heterostructures make it possible to engineer one of the largest known nonlinear optical responses in condensed matter systems--but this nonlinear response is limited to light with electric field polarized normal to the semiconductor layers. In a different context, plasmonic metasurfaces (thin conductor-dielectric composite materials) have been proposed as a way of strongly enhancing light-matter interaction and realizing ultrathin planarized devices with exotic wave properties. Here we propose and experimentally realize metasurfaces with a record-high nonlinear response based on the coupling of electromagnetic modes in plasmonic metasurfaces with quantum-engineered electronic intersubband transitions in semiconductor heterostructures. We show that it is possible to engineer almost any element of the nonlinear susceptibility tensor of these structures, and we experimentally verify this concept by realizing a 400-nm-thick metasurface with nonlinear susceptibility of greater than 5 × 10(4) picometres per volt for second harmonic generation at a wavelength of about 8 micrometres under normal incidence. This susceptibility is many orders of magnitude larger than any second-order nonlinear response in optical metasurfaces measured so far. The proposed structures can act as ultrathin highly nonlinear optical elements that enable efficient frequency mixing with relaxed phase-matching conditions, ideal for realizing broadband frequency up- and down-conversions, phase conjugation and all-optical control and tunability over a surface.
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33
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Robustness of Acoustic Scattering Cancellation to Parameter Variations. SUSTAINABILITY 2014. [DOI: 10.3390/su6074416] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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34
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Navau C, Prat-Camps J, Romero-Isart O, Cirac JI, Sanchez A. Long-distance transfer and routing of static magnetic fields. PHYSICAL REVIEW LETTERS 2014; 112:253901. [PMID: 25014816 DOI: 10.1103/physrevlett.112.253901] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Indexed: 06/03/2023]
Abstract
We show how the static magnetic field of a finite source can be transferred and routed to arbitrary long distances. This is achieved by using transformation optics, which results in a device made of a material with a highly anisotropic magnetic permeability. We show that a simplified version of the device, made by a superconducting-ferromagnet hybrid, also leads to an excellent transfer of the magnetic field. The latter is demonstrated with a proof-of-principle experiment where a ferromagnet tube coated with a superconductor improves the transfer of static magnetic fields with respect to conventional methods by a 400% factor over distances of 14 cm.
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Affiliation(s)
- C Navau
- Departament de Física, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Catalonia, Spain
| | - J Prat-Camps
- Departament de Física, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Catalonia, Spain
| | - O Romero-Isart
- Institute for Quantum Optics and Quantum Information of the Austrian Academy of Sciences, A-6020 Innsbruck, Austria and Institute for Theoretical Physics, University of Innsbruck, A-6020 Innsbruck, Austria
| | - J I Cirac
- Max-Planck-Institut für Quantenoptik, Hans-Kopfermann-Strasse 1, D-85748 Garching, Germany
| | - A Sanchez
- Departament de Física, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Catalonia, Spain
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Farhat M, Chen PY, Bağcı H, Enoch S, Guenneau S, Alù A. Platonic scattering cancellation for bending waves in a thin plate. Sci Rep 2014; 4:4644. [PMID: 24844801 PMCID: PMC4027886 DOI: 10.1038/srep04644] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2014] [Accepted: 03/24/2014] [Indexed: 11/09/2022] Open
Abstract
We propose an ultra-thin elastic cloak to control the scattering of bending waves in isotropic heterogeneous thin plates. The cloak design makes use of the scattering cancellation technique applied, for the first time, to the biharmonic operator describing the propagation of bending waves in thin plates. We first analyze scattering from hard and soft cylindrical objects in the quasistatic limit, then we prove that the scattering of bending waves from an object in the near and far-field regions can be suppressed significantly by covering it with a suitably designed coating. Beyond camouflaging, these findings may have potential applications in protection of buildings from earthquakes and isolating structures from vibrations in the motor vehicle industry.
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Affiliation(s)
- M. Farhat
- Division of Computer, Electrical, and Mathematical Sciences and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - P.-Y. Chen
- Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, TX, 78712, USA
| | - H. Bağcı
- Division of Computer, Electrical, and Mathematical Sciences and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - S. Enoch
- Aix-Marseille Université, CNRS, Centrale Marseille, Institut Fresnel, UMR 7249, 13013 Marseille, France
| | - S. Guenneau
- Aix-Marseille Université, CNRS, Centrale Marseille, Institut Fresnel, UMR 7249, 13013 Marseille, France
| | - A. Alù
- Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, TX, 78712, USA
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Kort-Kamp WJM, Rosa FSS, Pinheiro FA, Farina C. Tuning plasmonic cloaks with an external magnetic field. PHYSICAL REVIEW LETTERS 2013; 111:215504. [PMID: 24313504 DOI: 10.1103/physrevlett.111.215504] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Indexed: 06/02/2023]
Abstract
We propose a mechanism to actively tune the operation of plasmonic cloaks with an external magnetic field by investigating electromagnetic scattering by a dielectric cylinder coated with a magneto-optical shell. In the long wavelength limit, we show that the presence of a magnetic field may drastically reduce the scattering cross section at all observation angles. We demonstrate that the application of magnetic fields can modify the operation wavelength without the need of changing material and/or geometrical parameters. We also show that applied magnetic fields can reversibly switch on and off the cloak operation. These results, which could be achieved for existing magneto-optical materials, are shown to be robust to material losses, so that they may pave the way for developing actively tunable, versatile plasmonic cloaks.
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Affiliation(s)
- W J M Kort-Kamp
- Instituto de Física, Universidade Federal do Rio de Janeiro, Caixa Postal 68528, Rio de Janeiro 21941-972, Rio de Janeiro, Brazil
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Farhat M, Rockstuhl C, Bağcı H. A 3D tunable and multi-frequency graphene plasmonic cloak. OPTICS EXPRESS 2013; 21:12592-12603. [PMID: 23736478 DOI: 10.1364/oe.21.012592] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We demonstrate the possibility of cloaking three-dimensional objects at multi-frequencies in the far-infrared part of the spectrum. The proposed cloaking mechanism exploits graphene layers wrapped around the object to be concealed. Graphene layers are doped via a variable external voltage difference permitting continuous tuning of the cloaking frequencies. Particularly, two configurations are investigated: (i) Only one graphene layer is used to suppress the scattering from a dielectric sphere. (ii) Several of these layers biased at different gate voltages are used to achieve a multi-frequency cloak. These frequencies can be set independently. The proposed cloak's functionality is verified by near- and far-field computations. By considering geometry and material parameters that are realizable by practical experiments, we contribute to the development of graphene based plasmonic applications that may find use in disruptive photonic technologies.
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Affiliation(s)
- Mohamed Farhat
- Division of Computer, Electrical, and Mathematical Sciences and Engineering 4700 King Abdullah University of Science and Technology Thuwal 23955-6900, Saudi Arabia.
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Mühlig S, Cunningham A, Dintinger J, Farhat M, Hasan SB, Scharf T, Bürgi T, Lederer F, Rockstuhl C. A self-assembled three-dimensional cloak in the visible. Sci Rep 2013; 3:2328. [PMID: 23921452 PMCID: PMC3736173 DOI: 10.1038/srep02328] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Accepted: 07/15/2013] [Indexed: 11/17/2022] Open
Abstract
An invisibility cloak has been designed, realized and characterized. The cloak hides free-standing sub-wavelength three-dimensional objects at the short wavelength edge of the visible spectrum. By a bottom-up approach the cloak was self-assembled around the object. Such fabrication approach constitutes a further important step towards real world applications of cloaking; leaving the realm of curiosity. The cloak and the way it was fabricated opens an avenue for many spectacular nanooptical applications such as non-disturbing sensors and photo-detectors, highly efficient solar cells, or optical nanoantenna arrays with strongly suppressed cross-talk to mention only a few. Our results rely on the successful combination of concepts from various disciplines, i.e. chemistry, material science, and plasmonics. Consequently, this work will stimulate these fields by unraveling new paths for future research.
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Affiliation(s)
- Stefan Mühlig
- Institute of Condensed Matter Theory and Solid State Optics, Abbe Center of Photonics, Friedrich-Schiller-Universität Jena, 07743 Jena, Germany
- These authors contributed equally to this work
| | - Alastair Cunningham
- Département de Chimie Physique, Université de Genève, CH-1211 Genève 4, Switzerland
- These authors contributed equally to this work
| | - José Dintinger
- Optics & Photonics Technology Laboratory, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-2000 Neuchâtel, Switzerland
- These authors contributed equally to this work
| | - Mohamed Farhat
- Institute of Condensed Matter Theory and Solid State Optics, Abbe Center of Photonics, Friedrich-Schiller-Universität Jena, 07743 Jena, Germany
- Division of Computer, Electrical, and Mathematical Sciences and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955–6900, Saudi Arabia
| | - Shakeeb Bin Hasan
- Institute of Condensed Matter Theory and Solid State Optics, Abbe Center of Photonics, Friedrich-Schiller-Universität Jena, 07743 Jena, Germany
| | - Toralf Scharf
- Optics & Photonics Technology Laboratory, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-2000 Neuchâtel, Switzerland
| | - Thomas Bürgi
- Département de Chimie Physique, Université de Genève, CH-1211 Genève 4, Switzerland
| | - Falk Lederer
- Institute of Condensed Matter Theory and Solid State Optics, Abbe Center of Photonics, Friedrich-Schiller-Universität Jena, 07743 Jena, Germany
| | - Carsten Rockstuhl
- Institute of Condensed Matter Theory and Solid State Optics, Abbe Center of Photonics, Friedrich-Schiller-Universität Jena, 07743 Jena, Germany
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