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This article concerns the Cauchy problem for the fractional semilinear pseudo-parabolic equation. Through the Green’s function method, we prove the pointwise convergence rate of the solution. Furthermore, using this precise pointwise structure, we introduce a Sobolev space condition with negative index on the initial data and give the nonlinear critical index for blowing up.

WOS: 000478803200002, A novel shaped metamaterial sensor application which is designed to operate in X band is proposed. A new sample holder for easy operation is designed and placed just behind the proposed structure in X band. Since the adulteration of fuel with kerosene and ethanol is known method. This study is developed to give an alternative approach to the adulteration sensing studies. By having higher quality factors and wider bandwidth, when it is compared with similar metamaterial studies, proposed structure and design have lots of advantages as resolution, sensitivity and quality factor. Validation of the proposal has been performed in three steps, these steps are dielectric constant measurement by using Agilent 85070E dielectric measurement kit, simulation of the studies and experimental test study of the proposed structure with sensor layer. Obtained results shows us that this proposal can easily be adapted for different electrochemical sensing applications, if the dielectric constant is changing from 2 to 6. Another novel side of this study is application different type of adulteration examples as kerosene and ethanol as well as olive oil adulteration with cotton oil, presents mass application of metamaterials. (C) 2019 The Electrochemical Society., Scientific and Technological Research Council of TurkeyTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [117M855], We would like to thank the Scientific and Technological Research Council of Turkey (117M855) for the financial support.

A miniaturized antenna employing a negative index metamaterial with modified split-ring resonator (SRR) and capacitance-loaded strip (CLS) unit cells is presented for Ultra wideband (UWB) microwave imaging applications. Four left-handed (LH) metamaterial (MTM) unit cells are located along one axis of the antenna as the radiating element. Each left-handed metamaterial unit cell combines a modified split-ring resonator (SRR) with a capacitance-loaded strip (CLS) to obtain a design architecture that simultaneously exhibits both negative permittivity and negative permeability, which ensures a stable negative refractive index to improve the antenna performance for microwave imaging. The antenna structure, with dimension of 16 × 21 × 1.6 mm3, is printed on a low dielectric FR4 material with a slotted ground plane and a microstrip feed. The measured reflection coefficient demonstrates that this antenna attains 114.5% bandwidth covering the frequency band of 3.4–12.5 GHz for a voltage standing wave ratio of less than 2 with a maximum gain of 5.16 dBi at 10.15 GHz. There is a stable harmony between the simulated and measured results that indicate improved nearly omni-directional radiation characteristics within the operational frequency band. The stable surface current distribution, negative refractive index characteristic, considerable gain and radiation properties make this proposed negative index metamaterial antenna optimal for UWB microwave imaging applications.

A new, compact planar wideband negative index metamaterial based on a modified split ring resonator (SRR) is studied to enhance performance of ultrawideband antenna. A compact, metamaterial (MTM)-inspired microstrip antenna is presented for microwave imaging system (MIS) application. Two layers of left-handed metamaterial array (2 × 4) of the unit cell are placed on the radiating patch and the ground plane, respectively. Each left-handed metamaterial (LHM) unit cell was constructed by modifying a square split ring resonator (SRR), resulting in negative permeability and permittivity with a stable negative refractive index. The results shows that it has a significant impact on the performance of conventional patch antenna in terms of transmission co-efficient, efficiency and low loss. Compared to antenna without LHM, it is shown that the bandwidth is significantly broadened up to a few megahertz and becomes more convergent leading to the achievement of desired properties for ultra-wideband (UWB) applications leading to microwave imaging. The proposed MTM antenna structure is fabricated on commercially-available, flame-retardant material of size 26 × 22 × 1.6 mm3 with 4.6 dielectric constants, due to its low cost and convenience for making multilayer printed circuit boards (PCBs). The antenna achieves 3.1 GHz to 10.71 GHz of impedance bandwidth (−10 dB), which covers the full UWB band. The use of double-layer negative index MTM unit cells enhances UWB performance, and the improved radiation efficiency, nearly directional radiation pattern, acceptable gain, stable surface current and negative refractive index make this MTM antenna a suitable candidate for UWB applications.

WOS: 000413620600005, In this paper, chiral nihility based pressure, density, temperature and moisture content metamaterial sensor applications are investigated in detail. A "chiral nihility'' medium in which both the permittivity and the permeability tend to zero is investigated. Gammadion shaped resonators particularly designed for chiral nihility are introduced. Bandwidths and signal strengths show admissible results. Simulation and experimental results prove that chiral nihility occurred at the resonance frequencies when medium parameters are retrieved. The pressure and density sensor applications of the proposed sensor study are realized both numerically and experimentally, and the obtained results show good agreements with each other., TUBITAK [114E295], M.K and O.A. acknowledges the support of TUBITAK under the Projects No. 114E295.

WOS: 000373991200015, There are many studies in literature on chiral metamaterials (MTMs) to obtain large chiralities with dynamic optical activities. With this regard, this new generation planar chiral MTM study focuses on a small, non-dispersive (constant/flat) chirality admittance over an indicated frequency band which has not been investigated so far in literature. This new generation planar chiral MTM provides a small and a constant/fixed chirality which is mostly ignored by the scientists. This study numerically and experimentally investigates and examines these new generation MTMs based on circular split ring resonators (SRRs) with an increased capacitance in details. Obtained results show that the suggested structure can provide a small and constant/flat chirality admittance over a certain frequency band and hence it can be used to design myriad novel electromagnetic (EM) devices such as transmission and antireflection filters, polarization rotators for any desired frequency regions., TUBITAK [113E290]; Turkish Academy of Sciences, M. Karaaslan acknowledges the support of TUBITAK under the Project No. 113E290 and partial support of the Turkish Academy of Sciences.

Metamaterials are periodic sub wavelength composite structures how may have a negative permeability and / or a negative permittivity. If permittivity and permeability are negative simultaneously, we are in presence of what we called a negative index material, sometimes called “left hand media", capable of negative refraction. By controlling some of these properties, metamaterials allow us to obtained behavior nonexistent in nature. This opens the way to new applications. In this thesis, the use of dielectric materials is justified by the reduction of a major downside: losses. Thanks to the removal of ohmic losses specific to metallic materials. A thorough numerical study of dielectric resonators, basic components of "all-dielectric" metamaterials, was conducted using a finite element commercial software. This study highlighted, at the beginning of the terahertz range, a negative permeability, a negative permittivity and a negative index, for two special ceramics, well known in literature: SrTiO₃ and TiO₂. The parametric studies on these ceramics have allowed to put in clear the key role of the inter-modal coupling in order to obtain a negative index. We have also shown the unconventional nature of inter-modal coupling when the two modes concerned are different: one magnetic, other electric. There are in fact two different coupling regimes: a simple progressive shifting of both resonance modes, and then the apparition of degenerative regime, where both modes are at the same frequency for a long range, something not really common in the literature. In addition to this theoretical contribution, our parametric studies have proposed an alternative to the two resonators paradigm, showing the possibility to design a negative index metamaterial with a single bimodal cell in terahertz range., Les métamatériaux sont des structures composites périodiques sub-longueur d’onde pouvant posséder une perméabilité et/ou une permittivité négative. Si ces deux grandeurs sont négatives simultanément, nous sommes en présence d’un matériau à indice négatif, appelés parfois matériaux « main gauche », capable donc de réfraction négative. Par le contrôle de certaines propriétés de la matière les métamatériaux offrent ainsi des comportements inexistants dans la nature. Ceci ouvre ainsi la voie à de nouvelles applications. Dans cette thèse, l’utilisation de matériaux diélectriques se justifie par la réduction d'un inconvénient majeur, les pertes. On s’affranchie en effet de la limites des pertes ohmiques dans les matériaux métalliques. Une étude numérique approfondie des résonateurs diélectriques, composants de base des métamatériaux « tout-diélectrique », a été menée à l’aide d’un logiciel commercial d’éléments finis. Cette étude a permis de mettre en évidence à l’entrée de la gamme terahertz une perméabilité, une permittivité et un indice de réfraction négatifs, pour deux céramiques particulières : le SrTiO₃ et le TiO₂. Les études paramétriques effectuées sur ces deux céramiques ont permises de mettre en évidente le rôle primordial du couplage inter-modal dans l’obtention d’un indice négatif. Nous avons également montré le caractère non conventionnel du couplage inter-modal lorsque les deux modes sont de nature différente, l’un magnétique, l’autre électrique. Il existe en effet deux régimes de couplage distincts, l’un de simple rapprochement des modes de résonances, l’autre de dégénérescence des modes où ceux-ci restent à la même fréquence sur une large gamme, chose jusqu’alors peu visible dans la littérature. En plus de cet apport théorique, nos études paramétriques ont permis de proposer une alternative au paradigme à deux résonateurs, en montrant la faisabilité d’un métamatériau à indice négatif à l’aide d’une cellule élémentaire bimodale au térahertz.

One way to obtain materials with a negative index is to achieve media with doubly negative constitutive parameters. We show that the double negativity required for perfect (non-dissipative) media is not necessary for real passive (lossy) metamaterials, for which single negativity of one of the two constitutive parameters may be sufficient. The analysis is presented through original diagrammatic representations involving both the real and imaginary parts of the dynamic constitutive parameters for isotropic media. A valid demonstration for acoustic and electromagnetic metamaterials is supported by considering an actual soft 3D locally-resonant ultrasonic metafluid having a negative acoustic index while being a single-negative medium. The crucial role of the imaginary parts of the constitutive parameters is then discussed through its impact on the figure of merit. Finally, the analysis is extended to an example of an electromagnetic negative-index metamaterial exhibiting both single and double negativity.

We report the experimental realization of an optical metamaterial composed of a hexagonal array of coaxial plasmonic metal/insulator/metal waveguides that shows strong polarization-independent optical mode index dispersion in the ultraviolet/blue. The metamaterial is composed of silicon coaxes with a well-defined diameter in the range of 150–168 nm with extremely thin sidewalls (13–15 nm), embedded in a silver film, fabricated using a combination of electron beam lithography, physical vapor deposition, reactive ion etching, and focused ion beam polishing. Using a Mach–Zehnder interferometer the phase advance is measured on several metamaterial samples with different dimensions in the UV/visible part of the spectrum. For all geometries the spectral features as well as the geometry dependence of the data correspond well with numerical finite-difference time domain simulations and the calculated waveguide dispersion diagram, showing a negative mode index between 440 and 500 nm.

In this paper, experimental evidences about the resonance phenomena in a negative 2D photonic crystal are shown. Localized plasmon-like modes and guided mode resonances are detected in the reflectivity spectrum of a photonic crystal slab irradiated with out-of-plane incident radiation. The strong confinement of the radiation, in addition to the field enhancement, make photonic crystals a very appealing alternative to plasmonic substrates, avoiding the limits of absorption losses in metals. © The Authors. All rights reserved.

[ES] Esta tesina, tras una introducción teórica a los novedosos campos de los metamateriales y la plasmónica, describe los esfuerzos de investigación realizados por el autor para la ideación de un innovador metamaterial de índice negativo en el espectro visible con potencial para tener gran ancho de banda y carácter isotrópico. Se describe con detalle el proceso analítico de diseño y los resultados de las simulaciones electromagnéticas, así como las limitaciones que presenta la estructura ideada., [EN] This dissertation, after a theoretical introduction to the novel fields of metamaterials and plasmonics, describes the research efforts undergone by the author for the devise of an innovative negative index metamaterial in the visible spectrum, with potential to show a high bandwidth and an isotropic character. The analytical design process and the electromagnetic simulation results are described in detail, as well as the limitations presented by the conceived structure.

Thanks to Victor Veselago for his hypothesis of negative index of refraction, meta-materials — engineered composites — can be designed to have properties difficult or impossible to find in nature: they can have both electrical permittivity (ϵ) and magnetic permeability (μ) simultaneously negative. The metamaterials — henceforth negative-index materials (NIMs) — owe their properties to subwavelength structure rather than to their chemical composition. The tailored electromagnetic response of the NIMs has had a dramatic impact on classical optics: they are becoming known to have changed many basic notions related with electromagnetism. The present article is focused on gathering and reviewing fundamental characteristics of plasmon propagation in coaxial cables fabricated of the right-handed medium (RHM) (with ϵ > 0, μ > 0) and the left-handed medium (LHM) (with ϵ < 0, μ < 0) in alternate shells starting from the innermost cable. Such structures as conceived here may pave the way to some interesting effects in relation to, for example, optical science exploiting the cylindrical symmetry of coaxial waveguides that make it possible to perform all major functions of an optical fiber communication system in which the light is born, manipulated, and transmitted without ever leaving the fiber environment, with precise control over the polarization rotation and pulse broadening. This review also covers briefly the nomenclature, classification, potential applications, and the limitations (related, for example, to the inherent losses) of the NIMs and their impact on classical electrodynamics in general, and in designing the cloaking devices in particular. A recent surge in efforts on invisibility and the cloaking devices seems to have spoiled the researchers worldwide: proposals include not only a way to hide an object without having to wrap the cloak around it, but also to replace a given object with another, thus adding to the deception even further! All this is attributed as much to the fundamental as to the practical advances made in the fabrication and characterization of NIMs. The article concludes briefly addressing the anticipated implications of plasmon observation in the multicoaxial cables and suggesting future dimensions worth adding to the problem. The background provided is believed to make less formidable the task of future writers of reviews in this field.

Date of Conference: 8-12 April 2013 Chiral metamaterials are attractive for their intriguing properties such as negative refractive index, optical activity and circular dichroism, and asymmetric transmission. In this paper, we review the research we have conducted for the purpose of investigating these exciting properties. © 2013 EurAAP.

It is generally accepted that the magnetic component of light has a minor role in the light-matter interaction. The recent discovery of metamaterials has broken this traditional understanding, as both the electric and the magnetic field are key ingredients in metamaterials. The top-down technology used so far employs noble metals with large intrinsic losses. Here we report on a bottom-up approach for processing metamaterials based on suspensions of monodisperse full dielectric silicon nanocavities with a large magnetic response in the near-infrared region. Experimental results and theory show that silicon-colloid-based liquid suspensions and photonic crystals made of two-dimensional arrays of particles have strong magnetic response in the near-infrared region with small optical losses. Our findings might have important implications in the bottom-up processing of large-area low-loss metamaterials working in the near-infrared region. © 2013 Macmillan Publishers Limited. All rights reserved.

Materials are generally classified in terms of their constitutive parameters, the complex permittivity and permeability , in the frequency domain. These parameters are used to determine the response of materials to electromagnetic (EM) radiation. Materials found in nature have positive real parts for both and . In recent years, researchers have shown that a new class of materials called metamaterials (MTMs), characterized by inclusions of various shapes and materials that are small compared to wavelength, result in an effectively homogeneous medium with the unique properties of negative real and which cause EM waves traveling through the medium to exhibit unusual characteristics. Zero specular reflection layers for four material types such as double positive (DPS), double negative (DNG), epsilon-negative (ENG) and mu-negative (MNG) materials are examined in this thesis. For each defined type of MTM, the transcendental equations are derived and solved numerically to generate curves for zero specular reflection. A MATLAB program was developed to generate universal curves for DPS, DNG, ENG, and MNG materials. The results were discussed and evaluated to determine wave behavior in each type of MTM as well as how they can be used as a matched-surface radar-absorbing material (RAM) for military application. The results were compared to published data. http://archive.org/details/universalzerospe1094517469 Civilian, Singapore Technologies Marine Ltd Approved for public release; distribution is unlimited.

The objective of this thesis is to investigate a new design of periodic metamaterial (MTM) structure for radar cross-section (RCS) reduction application on aircraft and ships. MTMs are man-made materials, not found in nature, that exhibit unusual properties in the radio-, electromagnetic-, and optical-wave bands. The cells of these periodic MTM structures must be much smaller than the wavelength of the frequency of interest. In a MTM, the structure and dimensions of the design at the frequency of interest can produce negative values of permeability and/or permittivity, which define the electrical properties of the MTM. This study looks at various designs of absorbing layers presented in technical papers and verifies the results in simulations. Modifications are done to the existing designs to achieve good absorption level at the radar-frequency band of interest. Modeling and simulation are done in Microwave Studio by Computer Simulation Technology (CST). The S-parameters S11 (reflection coefficient) and S12 (transmission coefficient) are used to investigate the performance of the MTM as a radar-frequency absorber. http://archive.org/details/metamaterialforr1094517465 Civilian, Singapore Technologies Aerospace Ltd. Approved for public release; distribution is unlimited.

A composite chiral metamaterial (CCMM) is designed and studied both numerically and experimentally. The CCMM is constructed by the combination of a continuous metallic wires structure and a purely chiral metamaterial (CMM) that consists of conjugated Rosettes. For the CMM, only very small, useful bands of negative index can be obtained for circularly polarized waves. These bands are all above the chiral resonance frequencies because of the high value of the effective parameter of relative permittivity epsilon. After the addition of the continuous metallic wires, which provide negative permittivity, the high value of epsilon can be partially compensated. Thus, a negative index band for the left circularly polarized wave that is below the chiral resonance frequency is obtained for the CCMM. At the same time, a negative index band for the right circularly polarized wave that is above the chiral resonance frequency is also obtained. Furthermore, both negative index bands correspond to the transmission peaks and have high values of the figure of merit. Therefore, the CCMM design that is proposed here is more suitable than the CMM for the construction of chiral metamaterials with a negative index. (C) 2012 Optical Society of America

We consider a Kerr-type nonlinear guiding layer surrounded by at least one medium made of a negative index material (NIM). Three different structures are investigated in this work. The first structure has a NIM cladding, the second has a NIM substrate, and the third has a NIM substrate and cladding. Three normalized parameters are used to study the dispersion characteristics of these waveguide structures. The dispersion curves are obtained and the effect of the NIM parameters on the guidance properties is presented. It is found that the dispersion characteristic of nonlinear waveguide structure with NIM cladding and dielectric substrate are similar to those for the same structure with NIM substrate and dielectric cladding. However, when both of them are NIMs new properties can be seen.

We consider a Kerr-type nonlinear guiding layer surrounded by at least one medium made of a negative index material (NIM). Three different structures are investigated in this work. The first structure has a NIM cladding, the second has a NIM substrate, and the third has a NIM substrate and cladding. Three normalized parameters are used to study the dispersion characteristics of these waveguide structures. The dispersion curves are obtained and the effect of the NIM parameters on the guidance properties is presented. It is found that the dispersion characteristic of nonlinear waveguide structure with NIM cladding and dielectric substrate are similar to those for the same structure with NIM substrate and dielectric cladding. However, when both of them are NIMs new properties can be seen.

We investigate the optical properties of metamaterials formed by collections of three-dimensional clusters of plasmonic nanoparticles. This type of nanoclusters (NCs) consist of spherical constellations of metallic nanospheres arranged around a central dielectric sphere and support collective plasmon modes among which the most relevant are those associated with the induced electric and magnetic dipole resonances. We discuss the effective electric and magnetic polarizabilities of NCs, emphasizing their isotropic properties, and we show that dense packed arrays of NCs can be used to realize metamaterials with negative effective permittivity and permeability, and even negative effective refractive index at visible frequencies. © 2011 IEEE.

We experimentally demonstrate a low-loss multilayered metamaterial exhibiting a double-negative refractive index in the visible spectral range. To this end, we exploit a second-order magnetic resonance of the so-called fishnet structure. The low-loss nature of the employed magnetic resonance, together with the effect of the interacting adjacent layers, results in a figure of merit as high as 3.34. A wide spectral range of negative index is achieved, covering the wavelength region between 620 and 806 nm with only two different designs. © 2011 American Physical Society., Financial support by the Spanish MICINN (Contracts No. CSD2008-00066 and No. TEC2008-06871-C02) and by the Valencian government (Contract No. PROMETEO-2010-087) is acknowledged. C.G.-M. acknowledges financial support from Grant FPU of MICINN. W.D. and A.Z. acknowledge financial support from EPSRC (U.K.).