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Article
Publication date: 19 June 2017

Robert Bogue

This paper aims to provide a technical insight into a selection of recent developments of sensor based on metamaterials.

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Abstract

Purpose

This paper aims to provide a technical insight into a selection of recent developments of sensor based on metamaterials.

Design/methodology/approach

Following a short introduction, this first part discusses sensors based on acoustic metamaterials. It then briefly considers negative index materials and split ring resonators and provides examples of sensors based on metamaterials which interact with electromagnetic radiation in the microwave, terahertz and infra-red regions. Finally, brief concluding comments are drawn.

Findings

Since their discovery at around the turn of the century, metamaterials have been studied widely by the research community. A diverse range of sensors and imaging devices have since been developed which exploit the unique properties of these materials and respond to physical, chemical and biological variables. Many exhibit characteristics and capabilities with the potential to overcome the limitations of conventional devices.

Originality/value

This provides details of a range of recently developed sensors based on the newly discovered families of metamaterials.

Details

Sensor Review, vol. 37 no. 3
Type: Research Article
ISSN: 0260-2288

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Article
Publication date: 17 December 2018

A. Vivek, K. Shambavi and Zachariah C. Alex

This paper aims to focus on research work related to metamaterial-based sensors for material characterization that have been developed for past ten years. A decade of…

Abstract

Purpose

This paper aims to focus on research work related to metamaterial-based sensors for material characterization that have been developed for past ten years. A decade of research on metamaterial for sensing application has led to the advancement of compact and improved sensors.

Design/methodology/approach

In this study, relevant research papers on metamaterial sensors for material characterization published in reputed journals during the period 2007-2018 were reviewed, particularly focusing on shape, size and nature of materials characterized. Each sensor with its design and performance parameters have been summarized and discussed here.

Findings

As metamaterial structures are excited by electromagnetic wave interaction, sensing application throughout electromagnetic spectrum is possible. Recent advancement in fabrication techniques and improvement in metamaterial structures have led to the development of compact, label free and reversible sensors with high sensitivity.

Originality/value

The paper provides useful information on the development of metamaterial sensors for material characterization.

Details

Sensor Review, vol. 39 no. 3
Type: Research Article
ISSN: 0260-2288

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Article
Publication date: 27 January 2020

Guochang Lin, Chaonan Hu, Lin Cong and Yongtao Yao

The purpose of this paper is to developing a kind of acoustic metamaterial with wide frequency band especially in low frequency region. At the same time, its the…

Abstract

Purpose

The purpose of this paper is to developing a kind of acoustic metamaterial with wide frequency band especially in low frequency region. At the same time, its the tunability of sound insulation frequency is achieved.

Design/methodology/approach

A three-dimensional (3D) acoustic metamaterial consisting of rigid frame, spherical attachment and thin film is proposed. The material parameters and the effect of the attachment hole on the forbidden band are investigated by finite element simulation. The sound insulation effect of the structure is validated by the combination of simulation and experiment.

Findings

The results show that the elastic modulus of the structural material determines the initial frequency of the forbidden band of the proposed 3D acoustic metamaterials. The lower the elastic modulus of the structural material, the lower the initial frequency of the forbidden band. The material parameters of the frame mainly affect the initial frequency of the first forbidden band, and the material parameters of the attachment will affect both the initial and termination frequency of the first forbidden band. Holes in the attachments reduce the band gap width. The characteristic curve moves down with the increase of subtracted mass.

Research limitations/implications

The findings may greatly benefit the application of the acoustic metamaterials in the fields of sound insulation and noise reduction.

Originality/value

This acoustic metamaterial structure has excellent sound insulation performance. At the same time, the single cell structure can be assembled into any shape. The structure can achieve sound selective filtering and combination control.

Details

Pigment & Resin Technology, vol. 50 no. 5
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 7 November 2016

Michail G. Christodoulou, Antonios X. Lalas, Nikolaos V. Kantartzis and Theodoros D. Tsiboukis

Metamaterials have been utilised in several exciting configurations such as tuneable reflectors, reconfigurable absorbers, and programmable modulators, triggering intense…

Abstract

Purpose

Metamaterials have been utilised in several exciting configurations such as tuneable reflectors, reconfigurable absorbers, and programmable modulators, triggering intense research efforts. Among them, the ability to steer the radiation pattern of a single antenna component by employing a metamaterial-based superstrate is considered crucial for the development of advanced beam forming applications. The purpose of this paper is to introduce an adjustable omega-inspired metamaterial module to facilitate the design of beam steering implementations, involving beam forming capabilities, as well.

Design/methodology/approach

A variable capacitive diode is properly positioned at the novel omega element, hence advancing the controllability of its electromagnetic performance and circumventing the requirement of extra bias networks. When an array of these particles is placed in front of an antenna, several negative refractive index profiles can be realised, allowing the manipulation of the beam direction. Furthermore, a pyramidal horn antenna, loaded with this complex medium superstrate, is thoroughly investigated in terms of programmable beam steering and beam forming attributes. Several numerical data derived via the finite element method unveil the merits of the featured configuration.

Findings

The proposed structure allows programmability of the electromagnetic behaviour, but also circumvents the necessity of complicated bias networks, while minimising interference. The numerical assessment of a standard gain pyramidal horn antenna, associated to the featured metamaterial superstrate, sufficiently proves the controllable beam steering and beam forming attributes. Several parametric studies clarify the principal characteristics of the proposed setup, facilitating the design of high-end systems.

Originality/value

Development of tuneable metamaterial, which utilises variable capacitive diodes to enable controllability. Incorporation of reconfigurable metamaterials into antenna technology. Design of a pyramidal horn antenna, loaded with a complex medium superstrate exhibiting programmable beam steering and beam forming attributes. The proposed device circumvents the necessity of complicated bias networks, while minimising interference.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 35 no. 6
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 27 September 2011

Oleg Rybin, Konstantin Yemelyanov, Amjad Pitafi and Tahira Nawaz

The purpose of this paper is to study the microwave behaviour of effective magnetic permeability for two‐component ferrite like metamaterial medium in the direction of a…

Abstract

Purpose

The purpose of this paper is to study the microwave behaviour of effective magnetic permeability for two‐component ferrite like metamaterial medium in the direction of a biasing magnetic field. The metamaterial medium is presented as an infinite host dielectric material (air) with periodically embedded ferric cylindrical and spherical inclusions saturated with an external dc magnetic field. The study is based on the effective medium theory developed for polycrystalline metaferrites. The simulations show that the presented metamaterial can exhibit the ultra‐low refractive index (ULI) phenomenon and the phenomenon of negative magnetic permeability for the case of microwave propagation in the direction of bias.

Design/methodology/approach

The obtained results are based on the wave long approximation of permeability tensor of the presented metamaterial media obtained earlier by the first author. Using the standard approach, the authors apply the above expressions for the microwave propagation in direction of biasing dc magnetic field considering different polarization of the incident microwave.

Findings

The considered artificial material media can become either material with a ULI or with negative values in the GHz frequencies.

Originality/value

The paper is concerned with part of the theory of a new generation of artificial ferrites.

Details

Multidiscipline Modeling in Materials and Structures, vol. 7 no. 3
Type: Research Article
ISSN: 1573-6105

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Article
Publication date: 11 November 2013

Alessio Monti, Luca Scorrano, Simone Tricarico, Filiberto Bilotti, Alessandro Toscano and Lucio Vegni

The purpose of this paper is to show how metamaterials with extreme values of permittivity and permeability, may be effectively used to design artificial magnetic…

Abstract

Purpose

The purpose of this paper is to show how metamaterials with extreme values of permittivity and permeability, may be effectively used to design artificial magnetic conductors (AMC) at a given frequency. In particular, this paper theoretically determines, for the different polarizations of the incidence field, the conditions under which metamaterials can behave as an AMC.

Design/methodology/approach

In order to find out the required values of the constitutive parameters, this paper has done a theoretical analysis based on the transmission-line theory. The obtained analytical reflection coefficient has been particularized for the different possible polarizations of the incidence field in order to find the constitutive parameters values that this paper needs for the AMC behavior.

Findings

Depending on the polarization of the field, it is shown that different values of the constitutive parameters are needed to get AMCs. In particular, it is shown that in the case of TEM and TE polarizations, a large value of the permeability is enough to obtain an AMC boundary condition. In the case of the TM polarization, instead, the AMC boundary condition is effectively achieved by using a material with vanishing permittivity. The role of the permittivity in the three polarizations is discussed. Finally, possible implementations and applications at microwave and optical frequencies are presented.

Originality/value

The idea of using miniaturized inclusions to obtain AMCs is not completely new. However, to the authors' best knowledge, a complete and rigorous theoretical analysis showing the capabilities and the limits of this approach has not yet been presented in the open technical literature.

Details

COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering, vol. 32 no. 6
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 14 November 2008

Giacomo Oliveri and Mirco Raffetto

The paper's purpose is to deduce additional information on the accuracy of finite element simulators for electromagnetic problems involving effective models of metamaterials.

Abstract

Purpose

The paper's purpose is to deduce additional information on the accuracy of finite element simulators for electromagnetic problems involving effective models of metamaterials.

Design/methodology/approach

The objective is achieved by solving, with a well known commercial simulator, many different configurations of two types of electromagnetic problems: a free‐space scattering by a sphere and a waveguide discontinuity problem. Such problems are known to be able to point out the difficulties of numerical simulators. On the other hand, they are representative of two important classes of problems and can provide indications on what can happen in other cases.

Findings

This analysis confirms that the numerical errors can be important just in close proximity of the interface between metamaterials and standard media. Small values of loss tangents can be sufficient to obtain very accurate results. Adaptive mesh generators should not be used in the presence of negligible values of the loss tangents. For more uniform meshes the results are satisfactory, with sufficiently fine meshes. When the magnitude of the real parts of the effective dielectric permittivity of a metamaterial and of the adjacent standard media are significantly different, the accuracy is satisfactory in any case.

Research limitations/implications

The results are obtained by considering problems of two types. There is no guarantee that all the deductions apply to other models.

Practical implications

To design practical devices involving metamaterials reliable electromagnetic simulators are necessary. The reported results seem to indicate that it is possible to adopt some countermeasures against the possible lack of accuracy of finite element simulators in the presence of effective models of metamaterials.

Originality/value

For the first time, to the best of authors' knowledge, an extensive analysis on the accuracy of finite element simulators for critical problems involving metamaterials has been carried out. Some simple suggestions to improve their reliability in these cases are provided.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 27 no. 6
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 15 July 2020

Elakkiya A., Radha Sankararajan, Sreeja B.S. and Manikandan E.

A novel and simple six-band metamaterial absorber is proposed in the terahertz region, which is composed of an I-shaped absorber and circular ring with four gaps and a…

Abstract

Purpose

A novel and simple six-band metamaterial absorber is proposed in the terahertz region, which is composed of an I-shaped absorber and circular ring with four gaps and a continuous metal ground plane separated by only 0.125 mm polyimide dielectric substrate. Initially, I-shaped resonator gives three bands at 0.4, 0.468 and 0.4928 THz with the absorptivity of 99.3%, 97.9% and 99.1%, respectively. The purpose of this paper is to improve the number of bands, for which the authors added the circular ring with four gaps, so the simulated metamaterial absorber exhibited six absorption peaks at 0.3392, 0.3528, 0.3968, 0.4676, 0.4768 and 0.492 THz, with the absorption rate of 91.4%, 94.2%, 94.9%, 90.3%, 77.5% and 97.4%, respectively. The surface current distribution and angle independence are explained for all the six frequencies which are used to analyze the absorption mechanism clearly. Structure maximum uses the squares and circles, so it will make the fabrication easy. The multiband absorbers obtained here have potential applications in many engineering technology, thermal radiation, material detection and imaging and optoelectronic areas.

Design/methodology/approach

This paper presents the design of the six-band metamaterial absorber which is from the I-shaped resonator and circular ring with four gaps and the metallic ground plane separated by the 0.125 polyimide dielectric substrate. The absorber exhibited six absorption peaks at 0.3392, 0.3528, 0.3968, 0.4676, 0.4768 and 0.492 THz, with the absorption rate of 91.4%, 94.2%, 94.9%, 90.3%, 77.5% and 97.4%, respectively. From the fabrication point of view, the proposed six-band metamaterial absorber has a very simple geometrical structure, and it is very easy to be fabricated.

Findings

The authors present a new and simple design of six-band absorber based on an I-shaped absorber and circular ring with four gaps and a metallic ground plane separated by a polyimide layer having the thickness of 0.125 mm. Six different resonance absorption peaks are found at 0.3392, 0.3528, 0.3968, 0.4676 , 0.4768 and 0.492 THz. Surface current distribution and angle independence plot have been studied to understand the absorption behavior of the designed terahertz metamaterial absorber.

Originality/value

The multiband absorbers obtained here have potential applications in many engineering technology, thermal radiation, material detection, security, sensors, imaging and optoelectronic areas.

Details

Circuit World, vol. 46 no. 4
Type: Research Article
ISSN: 0305-6120

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Article
Publication date: 11 November 2013

Kamil Boratay Alici, Mehmet Deniz Caliskan, Filiberto Bilotti, Alessandro Toscano, Lucio Vegni and Ekmel Ozbay

Metamaterial unit cells composed of deep subwavelength resonators brought up new aspects to the antenna miniaturization problem. The paper experimentally demonstrates a…

Abstract

Purpose

Metamaterial unit cells composed of deep subwavelength resonators brought up new aspects to the antenna miniaturization problem. The paper experimentally demonstrates a metamaterial-inspired miniaturization method for circular patch antennas. In the proposed layouts, the space between the patch and the ground plane is filled with a proper metamaterial composed of either multiple split-ring or spiral resonators (SRs). The authors have manufactured two different patch antennas, achieving an electrical size of λ/3.69 and λ/8.26, respectively. The paper aims to discuss these issues.

Design/methodology/approach

The operation of such a radiative component has been predicted by using a simple theoretical formulation based on the cavity model. The experimental characterization of the antenna has been performed by using a HP8510C vector network analyzer, standard horn antennas, automated rotary stages, coaxial cables with 50 Ω characteristic impedance and absorbers. Before the characterization measurements we performed a full two-port calibration.

Findings

Electrically small circular patch antennas loaded with single layer metamaterials experimentally demonstrated to acceptable figures of merit for applications. The proposed miniaturization technique is potentially promising for antenna applications and the results presented in the paper constitute a relevant proof for the usefulness of the metamaterial concepts in antenna miniaturization problems.

Originality/value

Rigorous experimental characterization of several meta material loaded antennas and proof of principle results were provided.

Details

COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering, vol. 32 no. 6
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 4 July 2016

Antonios X. Lalas, Nikolaos V. Kantartzis and Theodoros D. Tsiboukis

Metamaterials are artificially tailored complex media with extraordinary properties, not available in nature. Due to their unique performance, they are considered as a…

Abstract

Purpose

Metamaterials are artificially tailored complex media with extraordinary properties, not available in nature. Due to their unique performance, they are considered as a crucial component of modern radio-frequency technology, especially in the THz regime. However, their lack of wide spectral bandwidths introduce constraints for realistic applications. The purpose of this paper is to propose piezoelectric micro-electromechanical systems (MEMS) actuators to modify the shape of electric field-driven LC (ELC) resonators. A THz modulation capability is revealed by connecting/disconnecting the associated metal parts.

Design/methodology/approach

Piezoelectric MEMS actuators are proposed to provide the desired bandwidth enhancement along with THz modulation. Two setups with different degrees of freedom in altering the behaviour of the novel modulator are investigated. A variety of numerical data, acquired via the finite element method, substantiate the advantageous characteristics of the proposed structures.

Findings

The novel devices enable the modification of the structural features of an ELC-based complex medium, unveiling in this manner a significant THz modulation capability along with improved bandwidth tunability. Two discrete cases are presented involving different degrees of freedom to shape the overall performance of the metamaterial modulator.

Originality/value

Development of a THz modulator, which utilises metamaterials as its fundamental component. Incorporation of tunable piezoelectric metamaterials into THz technology allowing increased reconfigurability. Bandwidth enhancement of metamaterial systems and alternative design via multiple controllable gaps enabling more degrees of freedom for design purposes.

Details

COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering, vol. 35 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

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