147 results on '"left-handed material"'
Search Results
2. Frequency shifting of plasmon polariton defect modes in a non-Hermitian finite heterostructure.
- Author
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Silva, A.G., Costa, A.E.B., Brandão, P.A., and Cavalcanti, S.B.
- Subjects
- *
ELECTROMAGNETIC waves , *METAMATERIALS , *OPTICAL properties , *POLARITONS - Abstract
A finite photonic layered system alternating usual media with a dispersive metamaterial with two central layers in a PT- symmetric arrangement is investigated under the oblique incidence of an electromagnetic wave. We have found a defect mode within the gap, and we have studied its optical properties under the influence of gain and loss distributed in these central layers. As a consequence of PT-symmetry in the system, we find that exceptional points can be attracted to or repelled from each other depending on which side of the frequency band under study. Below the plasmon frequency, repulsion occurs between pairs of exceptional points, while above it they attract each other. • Defect mode within the PP-gap. • Influence of the non-Hermiticity on the gap and defect properties. • Exceptional points can be attracted or repelled in layered systems with metamaterial inclusions. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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3. Research on the characteristics and equivalent circuits of left‐handed materials with the same manifestation.
- Author
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Hu, Yan, Sun, Jianfeng, Zhang, Zhen, Wang, Zhuopeng, and Wang, Xia
- Subjects
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DIPOLE antennas , *NEGATIVE refraction - Abstract
Two new types of heterogeneous left‐handed materials (LHM) are presented in this article. By combining the split resonant ring structure with the S‐shaped structure, a single‐sided printed heterogeneous type I LHM is designed; By rotating and combining the designed heterogeneous type I LHM, the heterogeneous type II LHM are formed. After electromagnetic simulation and S‐parameter extraction, it is confirmed that the heterogeneous type I LHM and the heterogeneous type II LHM have negative refraction characteristics at 1.8–2.3 and 2.5–3.2 GHz, respectively. After loading on the dipole antenna, the resonant frequency of the dipole antenna is reduced from 2.45 to 1.68 GHz, that is, loading heterogeneous type I and heterogeneous type II LHM can realize the miniaturization of the dipole antenna, which is 29.7% smaller than the previous design in terms of size reduction. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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4. One‐step leapfrog alternating direction implicit procedure for left‐handed material in open region problems with enhanced absorption.
- Author
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Wu, Shihong, Su, Feng, Liu, Lining, Dong, Yunyun, and Chen, Xiangguang
- Subjects
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DIPOLE antennas , *ABSORPTION - Abstract
By incorporating higher order formulation and one‐step leapfrog alternating direction implicit (ADI) procedure, unconditionally stable perfectly matched layer implementation is proposed for terminating frequency‐dependent left‐handed material in finite‐difference time‐domain lattice. To be more specific, frequency‐dependent left‐handed material can be calculated by the piecewise linear recursive convolution method. The proposed scheme shows advantages of higher order formulation and one‐step leapfrog ADI procedure in terms of enhancing absorbing performance, improving computational efficiency and simulating open region problems. The effectiveness is demonstrated through the computational domain with dipole antenna model above the left‐handed material slab. From results, it can be concluded that the proposed formulation can obtain considerable absorption, outstanding efficiency, and improved entire performance. Meanwhile, the proposed scheme also keeps its stability when time step far exceeds the Courant‐Friedrich‐Levy condition. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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5. Tuneable double negative (DNG) Tri-Hexagonal split ring resonator metamaterial for 5G application.
- Author
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Arbaatun Adawiah, Nurul, Salem Al-Bawri, Samir, Mohd Sahar, Norsuzlin, Tariqul Islam, Mohammad, and Singh, Mandeep S.J.
- Subjects
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METAMATERIALS , *5G networks , *NETWORK performance , *RESONATORS , *METAMATERIAL antennas , *UNIT cell - Abstract
• Compact Tunable negative Metamaterial for enhancing 5G network performance. • Frequency-Tunable Tri-Hexagon and Tri-Square Split Ring Resonator for Bandwidth Optimization. • Empowering 5G with Double Negative (DNG) Properties. • Fabrication of the proposed metamaterial experimental result to verify the overall performance. This paper introduces a compact tuneable metamaterial (MTM) unit cell featuring a tri-hexagon and tri-square split ring resonator (THTSSSR) structure designed for 5G communication applications. Metamaterials are employed to achieve unique electromagnetic properties not found in natural materials. The design process involves the arrangement of three square rings and three hexagon rings as metallic patches on a Rogers substrate (RT 5880), measuring 7 x 7 mm2 with a thickness of 1.575 mm. The proposed design exhibits double negative (DNG) properties, with resonances in the transmission coefficient (S21) at 3.493 GHz and a bandwidth of −10 dB covering frequencies between 3.057 and 3.711 GHz. Numerical simulations conducted using finite-integration techniques (FIT) in CST Microwave Studio validate the design's effectiveness, with confirmation through the Advanced Design System (ADS). The MTM unit cell demonstrates tuneable attributes, including negative permittivity ranging from 3.39 to 5 GHz and negative permeability from 3.39 to 3.86 GHz. These findings highlight the compactness and tunability of the proposed design, making it promising for 5G communication applications. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
6. Analysis of Coupled Surface Plasmon in LHM Mediated Dielectric Gap Multilayer Structure
- Author
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Mohammed Bendjebbour, Abdellatif Cherifi, and Benamar Bouhafs
- Subjects
Confined electromagnetic modes ,surface plasmon resonance sensor ,left-handed material ,Applied optics. Photonics ,TA1501-1820 - Abstract
Abstract The purpose of this work is to investigate theoretically the characteristics of confined electromagnetic modes propagating along the interfaces of a multilayer device. This one dimensional (ID) sensor is formed by stacking a left-handed material (LHM) layer between a SiCt2-glass prism and a dielectric gap layer in contact with gold (Au). The results indicate that the total thickness of the LHM layer and dielectric gap, in optimum conditions, give the ability of tuning significantly the characteristics of the resonant modes correlated to surface plasmons (SPs) propagation along the interfaces of the designed device. By considering two arrangements between LHM and Au, two opposite resonant behaviors observed in p-reflectance spectra are analyzed in the angular interrogation mode and discussed thoroughly.
- Published
- 2019
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7. Analysis of Coupled Surface Plasmon in LHM Mediated Dielectric Gap Multilayer Structure.
- Author
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Bendjebbour, Mohammed, Cherifi, Abdellatif, and Bouhafs, Benamar
- Subjects
SURFACE plasmons ,SURFACE analysis ,DIELECTRICS ,SURFACE plasmon resonance ,DIELECTRIC films ,CERAMIC capacitors - Abstract
The purpose of this work is to investigate theoretically the characteristics of confined electromagnetic modes propagating along the interfaces of a multilayer device. This one dimensional (ID) sensor is formed by stacking a left-handed material (LHM) layer between a SiCt
2 -glass prism and a dielectric gap layer in contact with gold (Au). The results indicate that the total thickness of the LHM layer and dielectric gap, in optimum conditions, give the ability of tuning significantly the characteristics of the resonant modes correlated to surface plasmons (SPs) propagation along the interfaces of the designed device. By considering two arrangements between LHM and Au, two opposite resonant behaviors observed in p-reflectance spectra are analyzed in the angular interrogation mode and discussed thoroughly. [ABSTRACT FROM AUTHOR]- Published
- 2020
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8. Dynamic Propagation of Quadratically Chirped Airy Beams in the Right-Handed and Left-Handed Material Slabs
- Author
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Zihao Pang, Jianbin Zhang, Tianfen Zhong, Liyan Feng, Linyi Wang, and Dongmei Deng
- Subjects
Beam propagation ,quadratic chirp ,left-handed material ,finite-energy Airy beams. ,Applied optics. Photonics ,TA1501-1820 ,Optics. Light ,QC350-467 - Abstract
We analytically and numerically investigate the dynamic propagation of the quadratically chirped Airy beams in right-handed material (RHM) and left-handed material (LHM) slabs. Based on the analytical expressions and numerical calculations, we find that through choosing the appropriate value of the quadratic chirp, one can modify the diffraction, the intensity distribution, the propagation path, and acceleration and deceleration of the quadratically chirped Airy beams to meet the actual usage accordingly. In addition, we also demonstrate the effect of the quadratic chirp on the Poynting vector and the angular momentum of the quadratically chirped Airy beams, respectively. Furthermore, we explore the gradient and scattering forces on a Rayleigh dielectric particles induced by the quadratically chirped Airy beams.
- Published
- 2017
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9. Low radar cross section microstrip antenna based on left‐handed material.
- Author
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Zhang, Jia Kai, Xu, Jia Chen, Ding, Jun, and Guo, Chen Jiang
- Subjects
- *
RADAR cross sections , *MICROSTRIP antennas , *RADAR antennas , *ELECTROMAGNETIC waves - Abstract
This article designs a hexagonal left‐handed material (LHM) and proposes a microstrip antenna with low radar cross‐section (RCS) based on this new LHM. The modified antenna RCS is significantly reduced without reducing radiation performance compared with two reference antennas. The scattering distribution shows the RCS reduction is attributable to the LHM. Antenna prototypes are fabricated and measured to verify the simulation. As a result, the modified antenna realized RCS reduction while maintaining radiation performance, with 19.5 dB maximum RCS reduction at 1.16 GHz, and the out‐of‐band RCS reduced due to the converged electromagnetic wave caused by the LHM. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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10. Comment on: "Tunable surface waves supported by graphene-covered left-handed material structures" [Opt. Commun. 489 (2021) 126874].
- Author
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Moradi, Afshin
- Subjects
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ELECTRICAL conductors , *ELECTROMAGNETIC wave propagation , *DISPERSION relations , *SURFACE waves (Seismic waves) , *PEOPLE with disabilities - Abstract
In a recent article (Yaqoob et al., 2021), Yaqoob et al. studied the tunable electromagnetic surface wave propagation on the graphene-covered left-handed material (LHM) slab backed by the perfect electric conductor (PEC). They derived the dispersion relations for both transverse electric (TE) and transverse magnetic (TM)-polarized surface waves, and then used the relations for two types of LHMs according to the spectral range, i.e., GHz- and THz-LHM. The present Comment points out although the system under consideration (i.e., graphene-covered LHM) is itself physically challenging, the results for THz-LHM are also rather unreal because the frequency regime to accomplish the calculations falls within the high THz frequency band. In such a frequency band, the conductor substrate no longer behaves like a PEC and thus the results are rather unreal when considering THz-LHM. We note that the metal, for example, gold or silver may be modeled as a PEC, but only for a few THz. Moreover, when considering GHz-LHM, we obtain new forms of dispersion relations for both TE and TM surface waves. We find that our dispersion relations do not agree with the results obtained by Yaqoob et al. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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11. Spherical Spiral Metamaterial Unit Cell for Negative Permeability and Negative Permittivity.
- Author
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Smith, Kathryn L. and Adams, Ryan S.
- Subjects
- *
RESONATORS , *METAMATERIALS , *PERMEABILITY , *ELECTRIC fields , *PERMITTIVITY - Abstract
This paper introduces a 3-D spherical spiral expansion of the split ring resonator (SRR) commonly used to achieve negative permeability. The spherical spiral unit cell is shown to produce negative permeability over a much wider bandwidth than the traditional SRRs, and also to be capable of producing wideband negative permittivity or a double-negative response, depending on the orientation of the unit cell with respect to the incident electric field. The current structures leading to this phenomenon are discussed. Simulated and measured results are presented. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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12. Ternary photonic crystal with left-handed material layer for refractometric application.
- Author
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Taya, S.A.
- Abstract
Graphical abstract Highlights • Ternary photonic crystal layer is examined for refractometric applications. • One of the layers is assumed to left-handed material (LHM). • The transmission spectrum is studied and found to exhibit a transmission peak. • The peak shift due to any change in the index of the analyte is investigated. • The peak shift can be enhanced with the change of the LHM parameters. Abstract A ternary photonic crystal with left-handed material (LHM) layer is examined for refractometric applications. One of the layers is assumed to be air and treated as an analyte. The transmittance from the ternary photonic crystal is studied in details and the wavelength shift due to the change in the refractive index of the analyte is investigated. The transmittance is investigated with the parameters of the LHM. It is found that the wavelength shift can be significantly enhanced with the decrease of both real part of the LHM permittivity and thickness. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
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13. Extension of energy band gap in ternary photonic crystal using left-handed materials.
- Author
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El-Amassi, Dena M., Taya, Sofyan A., Ramanujam, Nambi R., Vigneswaran, Dhasarathan, and Udaiyakumar, R.
- Subjects
- *
PHOTONIC crystals , *MAGNETIC permeability , *PHOTONIC band gap structures , *ENERGY bands , *ENERGY-band theory of solids - Abstract
We investigate the extension of energy band gap in one-dimensional ternary photonic crystal. We assume one of the layers constituting the ternary photonic crystal to be left-handed material (LHM) of simultaneously negative electric permittivity and magnetic permeability. The photonic crystal has the structure dielectric/LHM/dielectric. We show in this work, the energy band gap in one-dimensional ternary photonic crystal can be dramatically enlarged with the increase of the LHM layer thickness. Moreover, it can also be enlarged with the decrease of both the negative permittivity and permeability of the LHM layer. The effects of the angle of incidence and the number of layers are also investigated. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
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14. Low reflection and high transmission by a layered structure containing diamond-like carbon, porous silicon, and left-handed material.
- Author
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Ubeid, Muin F., Shabat, Mohammed M., and Altanany, Sameh M.
- Subjects
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CRYSTAL structure , *DIAMOND-like carbon , *POROUS silicon , *WAVEGUIDES , *ELECTROMAGNETIC wave propagation - Abstract
In this paper, we propose and theoretically analyze a stratified waveguide structure comprised of diamond-like carbon (DLC), porous silicon (PS), and left-handed material (LHM) subjected to incident light in order to achieve low reflection and high transmission. The proposed waveguide structure is situated between two half free spaces and a TE polarized plane wave incident on it. The main parameters of each material are given and the required equations for the electromagnetic plane wave propagation are presented. Transfer matrix method is implemented to find out the characteristics of the reflected and transmitted powers. In the numerical results, the mentioned powers are computed and illustrated as a function of the incidence angle, the frequency, and the slab thickness to demonstrate the main parameters for low reflection and high transmission. These theoretical parameters could be useful to the researchers and designers working in the area of solar cells and optical sensors. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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15. Topology optimization based methods and the realization programs for designing microstructures of patched metamaterials with prescribed electromagnetic properties.
- Author
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Shi, Pengfei, Gao, Renjing, and Liu, Shutian
- Abstract
This paper aims to establish a design tool to design the metamaterial microstructures with specific electromagnetic properties easily and conveniently, including the design methods of metamaterial microstructures and the corresponding program codes. For the patch type microstructure and several typical metamaterials (such as the single-negative metamaterials with specific negative permeability, left-handed metamaterials with specific material constants at the prescribed frequency; single negative metamaterials and left-handed metamaterials in prescribed frequency bands), the topology optimization models, solving schedules and corresponding implementation program codes for microstructure design are presented in detail. Several typical metamaterial microstructures with different design requirements are designed concretely. The results illustrated the correctness and validity of the design methods and the corresponding program codes. The designing method proposed and the program codes developed in this paper provide an effective tool for the design of metamaterial microstructure with specific function for the designers. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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16. Large positive and negative lateral shift in prism-waveguide system with left-handed material of weak absorption.
- Author
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Tang, Tingting, Liu, Wenli, and He, Xiujun
- Subjects
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OPTICAL waveguides , *ABSORPTION , *OPTICAL fiber cladding , *COMPUTER simulation , *OPTICAL materials - Abstract
We study the mechanism of large positive and negative lateral shift in a prism-waveguide coupling system where the guiding layer is composed of left-handed material with weak absorption. As the giant lateral shift is always dramatically decreased by the loss of guiding layer, we introduce lossy cladding layer and substrate to realize large lateral shift in the above system, theoretical expression of lateral shift is derived and simulation results illustrate the appearance of large lateral shift. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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17. Numeriska simuleringar av vågutbredning mellan ett vänsterhänt material och ett högerhänt material
- Author
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Rana, Balwan
- Subjects
Negativt-Index Material ,Steg-Index Gränssnitt ,Gradering-Index Gränssnitt ,Left-Handed Material ,RHM ,Step-Index Interface ,Electrical Engineering, Electronic Engineering, Information Engineering ,LHM ,Negative-Index Material ,NIM ,Analytical Solution ,Validering ,Backward- Wave Propagation ,PIM ,Högerhänt Material ,Right-Handed Material ,Validation ,Analytisk Lösning ,Graded-Index Interface ,Positivt-Index Material ,Bakåtvåg-utbredning ,Elektroteknik och elektronik ,Vänsterhänt Material ,Positive-Index Material - Abstract
The discovery of metamaterials has led to major advances in different fields of physics including optics, microwave engineering and acoustics. Specific to theoretical electromagnetism, the introduction of metamaterials have led to the development of negative-index materials (NIMs) with simultaneous negative permittivity and negative permeability with backward-wave propagation. In recent studies, exact analytical solutions for wave propagation from a step/graded-index interface between a right-handed material (RHM) and a left-handed material (LHM) have been obtained. This study attempts to provide numerical validation of the analytical solutions obtained by Dalarsson et al. by using the simulation tool CST. An square-SRR/strip-wire unit element was designed, with real part of relative permittivity equal to -1.96 and real part of relative permeability equal to -1.01. Such unit elements were orderly structured to produce a NIM structure. Furthermore, a positive-index material (PIM) structure was produced by reversing the sign of the material properties of the NIM. Both the results for the step- and graded-index interfaces have shown to possess backward-wave propagation for a normal incidence angle. The graded-index interface profiles have a more smooth and continuous wave propagation between the materials, which counteracts the effects of discontinuous material transitions present in step-index interface profiles. However, because the results of the present study were considerably affected by unwanted field effects, the analytical solutions are only qualitatively validated, and not validated in terms of their numerical accuracy. Upptäckten av metamaterial har lett till stora framsteg inom olika fysikområden inklusive optik, mikrovågsteknik och akustik. Specifikt för teoretisk elektromagnetism, har introduktionen av metamaterial lett till utvecklingen av negativa indexmaterial (NIM) med samtidig negativ permittivitet och negativ permeabilitet med bakåtvågsutbredning. I nyligen genomförda studier, har exakta analytiska lösningar för vågutbredning över ett steg-/graderat- indexgränssnitt mellan ett högerhänt material (RHM) och ett vänsterhänt material (LHM) erhållits. Denna studie försöker tillhanda-hålla numerisk validering, med hjälp av simuleringsverktyget CST, av de analytiska lösningar som erhållits av Dalarsson et al. En square-SRR/strip-wire enhetselement designades, med realdelen av relativ permittivitet lika med -1,96 och realdelen av relativ permeabilitet lika med -1,01. Sådana enhetselement strukturerades för att producera en materialstruktur med negativt index. Dessutom producerades en materialstruktur med positivt index (PIM) genom att vända tecknet av materialegenskaperna hos det negativa indexmaterialet (NIM). Både resultaten för steggränssnittet och det graderade indexgränssnittet har visat sig ha bakåtvågutbredning för vinkelrätt infall. De graderade indexgränssnittsprofilerna har en mer jämn och kontinuerlig vågutbredning mellan materialen, vilket motverkar effekterna av diskontinuerliga materialövergångar som finns i stegindexgränssnittsprofiler. Men eftersom resultaten av den aktuella studien påverkades avsevärt av oönskade fälteffekter, har de analytiska lösningarna validerats endast kvalitativt och valideras inte i termer av deras numeriska noggrannhet.
- Published
- 2021
18. Left-handed properties of a Fork-shaped metamaterial.
- Author
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Gao, Renjing, Shi, Pengfei, and Tang, Zhen-An
- Abstract
In this paper, we proposed a metamaterial with new single-sided Fork-shaped resonators. To verify and measure the left-handed properties, we conducted both simulations and experimental tests. With software Ansoft HFSS, we simulated the properties of the proposed metamaterial and obtained the scattering parameters (S-parameters), which illustrates that the new metamaterial exhibits left-handed property within certain frequency ranges. Then we obtain the magnitude of S21 parameter from experiment, which verified the existence of left-handed transmission peak and agreed with the simulation curve well. In addition, we studied how the scale of the unit cell of the metamaterial affected the left-handed frequency band. [ABSTRACT FROM PUBLISHER]
- Published
- 2011
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19. The Dynamical Study of the Metamaterial Systems.
- Author
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Jiang, Xunya, Liu, Zheng, Liang, Zixian, Yao, Peijun, Lin, Xulin, and Chen, Huanyang
- Abstract
We investigate the dynamical characteristics of metamaterial systems, such as the temporal coherence gain of superlens, the causality limitation on the ideal cloaking systems, the relaxation process and essential elements in the dispersive cloaking systems, and extending the working frequency range of cloaking systems. The point of our study is the physical dispersive properties of meta-materials, which are well known to be intrinsically strongly dispersive. With physical dispersion, new physical pictures could be obtained for the waves propagating inside metamaterial, such as the ˵group retarded time″ for waves inside superlens and cloak, the causality limitation on real metamaterial systems, and the essential elements for design optimization. So we believe the dynamical study of meta-materials will be an important direction for further research. All theoretical derivations and conclusions are demonstrated by powerful finite-difference time-domain simulations. [ABSTRACT FROM AUTHOR]
- Published
- 2010
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20. Review of experimental studies on microwave left-handed metamaterials.
- Author
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Ozbay, Ekmel and Aydin, Koray
- Subjects
- *
METAMATERIALS , *COMPOSITE materials , *MICROWAVES , *RESONATORS , *PHYSICS research - Abstract
We review experimental studies on left-handed metamaterials operating at microwave frequencies. Left-handed transmission is obtained from a composite metamaterial consisting of periodic split ring resonator and wire arrays. Phase measurements reveal that the left-handed metamaterial has a negative phase velocity and negative refraction. The negative index metamaterial is capable of imaging subwavelength features with a resolution of λ/8. [ABSTRACT FROM AUTHOR]
- Published
- 2007
- Full Text
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21. Rogue waves generation in a left-handed nonlinear transmission line with series varactor diodes.
- Author
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Onana Essama, B.G., Atangana, J., Biya Motto, F., Mokhtari, B., Eddeqaqi, N. Cherkaoui, and Kofane, Timoleon C.
- Subjects
- *
ROGUE waves , *NONLINEAR optics , *ELECTRIC lines , *VARACTORS , *ELECTROMAGNETIC waves , *SOLITONS - Abstract
We investigate the electromagnetic wave behavior and its characterization using collective variables technique. Second-order dispersion, first- and second-order nonlinearities, which strongly act in a left-handed nonlinear transmission line with series varactor diodes, are taken into account. Four frequency ranges have been found. The first one gives the so-called energetic soliton due to a perfect combination of second-order dispersion and first-order nonlinearity. The second frequency range presents a dispersive soliton leading to the collapse of the electromagnetic wave at the third frequency range. But the fourth one shows physical conditions which are able to provoke the appearance of wave trains generation with some particular waves, the rogue waves. Moreover, we demonstrate that the number of rogue waves increases with frequency. The soliton, thereafter, gains a relative stability when second-order nonlinearity comes into play with some specific values in the fourth frequency range. Furthermore, the stability conditions of the electromagnetic wave at high frequencies have been also discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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22. Fine control of filter performance based on composite right/left-handed metamaterial technology.
- Author
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Ahmed, Kafil Uddin and Virdee, Bal Singh
- Subjects
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METAMATERIALS , *UNIT cell , *DIELECTRICS , *BANDPASS filters , *CAPACITORS , *MICROFABRICATION , *CONSTRAINT satisfaction , *MICROSTRIP transmission lines - Abstract
Composite right/left-handed (CRLH) metamaterial unit cell whose ground-plane is defected with a rectangular dielectric slot is used to develop a single and multi-pole pole bandpass filter. The unit cell comprises of serially connected interdigital capacitors whose junction is connected to a short-circuited inductive stub. By defecting the ground-plane of the unit cell's structure with a dielectric slot, which is located immediately below the unit cell, enables substantial tuning of the filter's center frequency in the order of 26.5%. This is achieved with minimal effect on the unit cell's insertion and return-loss performance including its selectivity. The filters were fabricated on conventional dielectric substrate and their performance measured to verify the design methodology. The proposed technique eases the trade-off constraints and makes possible the realization of challenging filter specifications constituted from CRLH unit cells using distributed transmission-lines. © 2013 Wiley Periodicals, Inc. Int J RF and Microwave CAE 24:39-45, 2014. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
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23. Broadband and compact double negative composite metamaterials with low losses.
- Author
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Amiri, N., Forooraghi, K., and Atlasbaf, Z.
- Subjects
- *
BROADBAND communication systems , *METAMATERIALS , *COMPOSITE materials , *RESONATORS , *ELECTROMAGNETISM , *MICROFABRICATION , *NUMERICAL analysis - Abstract
In this paper two novel left-handed composite metamaterials consisting of SRRs, wire and single sided S-shaped resonators are proposed. One of them is a reduced-size resonator which uses superposition hypothesis to achieve adjacent resonances for a much broader negative refraction passband. The other is a modified planar structure with improved electromagnetic coupling and reduced electrical size. Both structures are truly matched to free space in almost whole left-handed frequency band. It will be shown that these metamaterials are robust to the fabrication errors of misalignment printing on both sides of the substrate. The superior performance of these structures are investigated numerically and experimentally and compared with the other split ring resonators. Wedge shape simulation and experimental results confirm the left-handed passband. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
24. Enhancement of lateral shift effect in a prism-waveguide system with lossy left-handed material by a loss compensation method.
- Author
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Tang, Tingting
- Subjects
- *
WAVEGUIDES , *SUBSTRATES (Materials science) , *SENSITIVITY analysis , *SIMULATION methods & models , *THICKNESS measurement , *OPTICAL fiber cladding - Abstract
Abstract: We study the large lateral shift in a prism-waveguide system with lossy left-handed material (LHM) guiding layer by use of a loss compensation method of cladding layer and substrate. The necessary conditions for the appearance of large lateral shift are obtained by theoretical analysis and simulation results demonstrate the validity of these conditions. Further calculation shows that in our system large lateral shift exhibits super-high sensitivity to the thickness change of cladding layer and substrate compared with other prism-waveguide systems with a guiding layer composed of thin metal or other ordinary materials. [Copyright &y& Elsevier]
- Published
- 2013
- Full Text
- View/download PDF
25. Planar waveguide with left-handed material guiding film for refractometry applications.
- Author
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EL-AGEZ, Taher M., TAYA, Sofyan A., SHABAT, Mohamed M., and KULLAB, Hani M.
- Subjects
- *
PLANAR waveguides , *REFRACTOMETERS , *SYMMETRY (Physics) , *REFRACTIVE index , *ENERGY conversion , *SENSITIVITY analysis , *DISPERSION relations - Abstract
A symmetric 3-layer slab waveguide with a left-handed material as a guiding layer is examined analytically for cover refractive index detection. The TM mode dispersion relation of the proposed waveguide is investigated. The sensitivity of the proposed sensor to changes in the cover refractive index and the power flowing within each layer are presented. Some unusual features are found; for example, the sensitivity of the proposed sensor is negative. Moreover, the sensitivity improvement compared with the conventional 3-layer waveguide sensor is approximately a factor of 6. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
26. Design, measurement, and characterization of dual-band left-handed metamaterials with combined elements.
- Author
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Min ‐ Hua, Li, He ‐ Lin, Yang, Hai, Lin, and Bo ‐ Xun, Xiao
- Subjects
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METAMATERIALS , *ELECTROMAGNETISM , *PARAMETER estimation , *PERMEABILITY , *DIPOLE moments , *ANTENNAS (Electronics) , *ELECTRIC filters , *MAGNETIC resonance , *NEGATIVE refraction - Abstract
We report on a new kind of planar left-handed metamaterial with both simulations and experiments in this article. Dual electric and magnetic resonance frequency bands are experimentally realized by introducing two different metallic elements in one unit cell, which offers a convenient approach in building dual-band or multiband negative-index metamaterials. The effective electromagnetic parameters obtained from the measured S-parameters indicate that negative refractive indexes are verified near 8.5 and 12 GHz with both negative permittivity and negative permeability. Field and current distribution at the dual resonances are also examined. At last, we calculated the radiated power of the magnetic dipole moments along y-axis. The idea can help us to fabricate dual-band or multiband metamaterial absorbers, filters, and antennas. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:493-497, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27399 [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
27. Maximum and Minimum Transmittance of a Structure Containing N-Identical Pairs of Left- and Right-Handed Materials.
- Author
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Ubeid, Muin F., Shabat, Mohammed M., and Sid-Ahmed, Mohammed O.
- Subjects
MAXWELL equations ,TRANSMITTANCE (Physics) ,NUMERICAL analysis ,ELECTRIC fields ,MAGNETIC fields - Abstract
The optical transmission properties of a structure consisting of N identical pairs of left- and right-materials are investigated theoretically and numerically. Maxwell's equations are used to determine the electric and magnetic fields of the incident waves at each layer. Snell's law is applied and the boundary conditions are imposed at each layer interface to calculate Fresnel coefficients. Expressions for reflectance and transmittance of the structure are given in terms of these coefficients. In the numerical results the transmittance of the structure is computed and illustrated as a function of frequency under different values of N. Minimum transmittance is achieved by using high and low opposite refractive indices of left and right materials of each pair of the structure. The frequency band of this transmittance is reduced by decreasing N. Maximum transmittance is demonstrated by using two slabs of the same width and opposite refractive indices placed between two dielectric media of the same kind. The effect of frequency and angle of incidence is very weak in these structures as compared to their all-dielectric counterparts. Moreover the obtained results are in agreement with the law of conservation of energy. [ABSTRACT FROM AUTHOR]
- Published
- 2012
28. Magnetic levitation from negative permeability materials
- Author
-
Coffey, Mark W.
- Subjects
- *
PERMEABILITY , *METAMATERIALS , *MAGNETIC suspension , *FORCE & energy , *MAGNETIC materials , *THICKNESS measurement - Abstract
Abstract: As left-handed materials and metamaterials are becoming more prevalent, we examine the effect of negative permeability upon levitation force. We first consider two half spaces of differing permeability and a point magnetic source, so that the method of images may be employed. We determine that the resulting force may be larger than for conventional magnetic materials. We then illustrate the inclusion of a finite sample thickness. [Copyright &y& Elsevier]
- Published
- 2012
- Full Text
- View/download PDF
29. Propagation of Airy beams from right-handed material to left-handed material.
- Author
-
Lin Hui-Chuan and Pu Ji-Xiong
- Subjects
- *
MATERIALS , *BENDING (Metalwork) , *REFRACTIVE index , *SHEAR waves , *BEAM dynamics - Abstract
Based on the ABCD matrix formalism, the propagation property of an Airy beam from right-handed material (RHM) to left-handed material (LHM) is investigated. The result shows that when the Airy beam propagates in the LHM, the intensity self-bending due to its propagation in the RHM can be compensated. In particular, if the propagation distance in the RHM is equal to that in the LHM and the refractive index of the LHM is nL = -1, the transverse intensity distribution of the Airy beam can return to its original state. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
30. Theoretical study of slab waveguide optical sensor with left-handed material as a core layer.
- Author
-
Taya, Sofyan A., El-Agez, Taher M., Kullab, Hani M., Abadla, Mazen M., and Shabat, Mohamed M.
- Subjects
- *
PLANAR waveguides , *DETECTORS , *REFRACTIVE index , *OPTICAL fiber cladding , *PERMITTIVITY - Abstract
A three-layer planar waveguide sensor consisting of thin left-handed material core layer is investigated for sensing applications. The sensitivity of the proposed sensor to the changes in the refractive index of the cladding is presented and studied for TE-polarized light. It is observed that the sensitivity of the proposed sensor is improved compared to that of the conventional three-layer slab waveguide sensor. It is also found that the sensitivity of the structure proposed is negative and critically dependent on the dispersive permittivity and permeability of the core layer. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
31. Numerical study of a structure containing left-handed material waveguide.
- Author
-
Ubeid, M., Shabat, M., and Sid-Ahmed, M.
- Abstract
In this paper a waveguide structure consisting of a pair of left-handed material (LHM) and dielectric slabs inserted in vacuum is investigated theoretically. Maxwell's equations are used to determine the electric and magnetic fields of the incident waves at each layer. Snell's law is applied and the boundary conditions are imposed at each layer interface to calculate the reflected and transmitted powers of the structure. Numerical results are illustrated to show the effects of frequency, angle of incidence and LHM thickness on the transmitted power when the refractive index of the dielectric layer changes. The same procedure is repeated to show the variation of the transmitted power with the change in the mentioned parameters under different values of dissipation factor of the lossy LHM. Consequently, two cases of the LHM are considered, loss-less case and loss case. The results obtained, are in agreement with the law of conservation of energy. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
32. Photonic Analog of Klein Paradox in a Periodic Layered Material with Composite Structure of Left-Handed Medium and Electromagnetically Induced Transparency.
- Author
-
Teh-Chau Liau, Jin-Jei Wu, Jian Qi Shen, and Tzong-Jer Yang
- Subjects
KLEIN paradox ,LAYER structure (Solids) ,COMPOSITE structures ,PHOTONICS ,ELECTROMAGNETIC induction ,TRANSPARENCY (Optics) ,BAND gaps - Abstract
A novel frequency-sensitive switching control effect induced by two-photon resonance for TM wave in a periodic layered medium containing left-handed material (LHM) and electromagnetically induced transparency (EIT) medium is suggested. Since the optical response of an atomic medium can be controlled via tunable quantum interference between multilevel transition pathways driven by an external control field, a periodic layered medium whose unit cells consist of left-handed medium and EIT atomic vapor can exhibit some intriguing properties: I) the band structure (and hence the reflection and transmission of light) will show flexible optical response sensitive to frequency, ii) an unusual Klein tunneling effect of light occurs in the present LHM-EIT-based medium, and iii) the controllable band structure depending on the external control field would have potential applications in designing new devices such as photonic switches, photonic logic gates and photonic transistors [ABSTRACT FROM AUTHOR]
- Published
- 2011
33. Dual bands of negative refractive indexes in the planar left-handed metamaterials
- Author
-
Li, Min-Hua, Yang, He-Lin, Tian, Yan, and Hou, Dong-Yun
- Subjects
- *
NEGATIVE refraction , *METAMATERIALS , *MAGNETIC resonance imaging , *ELECTROMAGNETISM , *PERMEABILITY , *ELECTRIC resonators - Abstract
Abstract: A kind of planar left-handed metamaterial (LHM) with unique configurations is demonstrated, which offers an approach in building dual-band negative-index materials. Simulated and experimental results predict two left-handed transmission bands near 11.1 and 14.6GHz. Dual bands of negative refractive indexes are verified using the retrieval procedure. Field and current distribution at the dual magnetic resonance are also examined. The effective electromagnetic parameters show that by carefully adjusting dimensions of the unit cell, electric and magnetic resonances can be coexistent at some frequency ranges with both negative permittivity and negative permeability. The idea can help us designing planar negative-index materials with multibands. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
34. Characteristics of Left-Handed Materials with Magnetic Resonance and Electric Anti-Resonance Based on Ceramics.
- Author
-
Lin-Li, Zhang, Zhuo, Xu, Shao-Bo, Qu, Xiao-Yong, Wei, An-Xue, Zhang, Song, Xia, and Feng, Xie
- Subjects
- *
MAGNETIC materials , *CERAMIC materials , *ELECTRIC properties , *MAGNETIC resonance , *PERMITTIVITY , *MAGNETIC permeability , *SUBSTRATES (Materials science) , *OPTICAL waveguides - Abstract
Based on ceramics S-shaped left-handed materials with magnetic resonance and electric anti-resonance were prepared by screen printing. The microwave transmittance properties of these samples in a rectangular waveguide were experimentally investigated. It is found that the two frequency bands of negative effective permittivity and negative effective permeability overlap from 8.5 to 9.46 GHz, which is left-handed materials pass-band and the bandwidth is about 1 GHz. Magnetic resonance is due to magnetic coupling between magnetic field component of external fields and the samples, in which the effective permeability could be negative. And electrical anti-resonance originated from electric coupling may contribute to negative effective permittivity. This based on ceramics substrate S-shaped construct possess both remarkable electric and magnetic resonances, which provides a flexible element for constructing planar left-handed materials. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
35. Metamaterial-based Broadband Elastic Wave Absorber.
- Author
-
PAI, P. FRANK
- Subjects
ELASTIC waves ,METAMATERIALS ,COMPOSITE materials ,FINITE differences ,NUMERICAL analysis - Abstract
This article presents modeling and analysis techniques for and reveals the actual working mechanism of longitudinal metamaterial bars as elastic wave absorbers. A metamaterial-based elastic wave absorber can be a uniform isotropic bar with many tiny spring-mass subsystems attached at separated longitudinal locations. In the literature, each cell that consists of a bar segment and an attached spring-mass subsystem is modeled as a discrete system of two degrees of freedom by integration and/or finite difference, and the idealized model becomes a dispersive medium for elastic waves and has a stop band that allows no waves to propagate forward. This work shows that these idealized models can be used only for elastic waves having wavelengths much longer than the unit cell's length. Moreover, it is revealed that a metamaterial-based elastic wave absorber is actually based on the concept of conventional mechanical vibration absorbers, which uses the local resonance of subsystems to generate inertia forces to work against the external load and prevent elastic waves from propagating forward. This concept is extended to design a broadband absorber that works for elastic waves of any wavelengths, including waves having wavelengths shorter than the unit cell's length. Numerical examples validate the design and reveal the cause of stop band. Moreover, the effect of negative effective mass and acoustic and optical modes are explained. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
36. Transmission and reflection properties of composite metamaterials in free space: Experiments and simulations.
- Author
-
Minhua Li and Helin Yang
- Subjects
- *
METAMATERIALS , *PERMITTIVITY , *REFRACTIVE index , *GEOMETRY , *MICROWAVES - Abstract
Free-space microwave measurements are applied on composite metamaterials (CMMs) consisting of split ring resonators (SRRs) and wires, also known as left-handed material. Our experiments are based on a type of CMMs with unique configurations and the transmission and reflection measurements performed in free space exhibit a pass band at about 9 GHz. Simulation results are also given, which are in good agreements with experiments. The widely belief of the pass band is that the stop bands of the SRRs alone and the wires alone constitute a clear demonstration of left-handed (LH) behavior. The LH behavior only take place in the medium with simultaneously negative permittivity ℇ, and permeability μ, also called double negative materials. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1865–1868, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24465 [ABSTRACT FROM AUTHOR]
- Published
- 2009
- Full Text
- View/download PDF
37. ABCD matrix formalism for propagation of Gaussian beam through left-handed material slab system
- Author
-
Zhou, Jianhua, Luo, Hailu, Wen, Shuangchun, and Zeng, Yangsu
- Subjects
- *
MATRIX mechanics , *GAUSSIAN beams , *CONSTRUCTION slabs , *OPTICAL phase conjugation , *OPTOELECTRONICS - Abstract
Abstract: We apply a simple ABCD matrix formalism to investigate beam propagation in left-handed material (LHM) slab systems. Firstly, we derive the expressions for the matrix elements for a single LHM slab. Based on the ABCD matrix, we obtain the field distributions both inside and outside the LHM slab, and the conditions for focusing and phase compensation of the Gaussian beam. Secondly, the derived ABCD law is applied to analyze the propagation properties of Gaussian beams through various cascaded LHM slab systems. The corresponding focusing and phase compensation conditions of the Gaussian beam are also obtained. Our theoretic formalism may be applied as a compact and effective tool for the research of light beam propagation in complex LHM slab systems, since it avoids the complicated integral operation. [Copyright &y& Elsevier]
- Published
- 2009
- Full Text
- View/download PDF
38. Unique properties of microwave in interlayer exchange-coupled trilayer ferromagnetic films associated with negative imaginary part of permeability
- Author
-
Chen, Jiangwei, Tang, Dongming, Zhang, Baoshan, Yang, Yi, Lu, Mu, and Lu, Huaixian
- Subjects
- *
MAGNETIC films , *FERROMAGNETIC materials , *MICROWAVES , *MAGNETIC permeability , *FERROMAGNETIC resonance , *MAXWELL equations , *ENERGY transfer - Abstract
Abstract: Based upon Landau–Lifshitz equation and Maxwell''s equations, we theoretically investigated properties of normally incident microwave propagation in interlayer exchange-coupled trilayer ferromagnetic film. It is found that, near resonance frequency of optic mode, imaginary part of permeability of one ferromagnetic layer is smaller than zero unusually, i.e., the ferromagnetic layer may be taken as an active medium. Thus a number of unique electromagnetic properties are presented, such as, the ferromagnetic layer becomes a left-handed material near low side of the resonance frequency of optic mode, and both phase velocity and time-averaged Poynting flow of the usually defined forward wave are negative simultaneously near high side of the resonance frequency. This work provides a feasible active medium to demonstrate the unique microwave properties. [Copyright &y& Elsevier]
- Published
- 2009
- Full Text
- View/download PDF
39. A magnetic field controlled negative-index microwave lens.
- Author
-
Petrov, R. V., Pandey, R., Srinivasan, G., and Bichurin, M. I.
- Subjects
- *
MICROWAVE lenses , *MAGNETIC fields , *RESONATORS , *FERRITES , *MICROWAVES - Abstract
A three-dimensional lens with magnetic field control of the index of refraction and focal length has been designed and characterized over 2-18 GHz. The lens is made of a lattice of cross-wire resonators and ferrite cubes. For the lattice without the ferrite cubes, a refractive index n ≈ -1 is measured at 11.25 GHz. With the introduction of ferrite cubes in the lattice, n could be tuned over the range -1.2 to +1.8 for nominal bias magnetic fields H. The focal point for the lens with n ≈ -1, for example, could be displaced by 2 cm by tuning H from 4100 to 4125 Oe. Theoretical estimates of the lens characteristics are in agreement with the data. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2804–2807, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23847 [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
- View/download PDF
40. Experimental study of quasi-one-dimensional comb-like photonic crystals containing left-handed material
- Author
-
Zhang, Liwei, Wang, Zhiguo, Chen, Hong, Li, Hongqiang, and Zhang, Yewen
- Subjects
- *
PERMITTIVITY , *ELECTRIC lines , *OPTICS , *OPTICAL instruments - Abstract
Abstract: Quasi-one-dimensional comb-like photonic crystals with backbone waveguide made of left-handed material are physically fabricated by using transmission lines. The transmission properties are experimentally investigated and it is found that the structures possess a special band gap. The gap does not originate from the conventional Bragg scattering mechanism in that it is invariant with the change of scale length. Moreover, the experimental results indicate that the gap-edges are determined by zero-average permittivity of the branch and backbone and zero permeability of backbone, respectively. Because of the characteristics, it will be convenient to realize a special gap using in microwave and optical engineering. [Copyright &y& Elsevier]
- Published
- 2008
- Full Text
- View/download PDF
41. Goos–Hänchen shift of the uniaxially anisotropic left-handed material film with an arbitrary angle between the optical axis and the interface
- Author
-
Wang, Z.P., Wang, C., and Zhang, Z.H.
- Subjects
- *
THIN films , *RESONANCE , *SOLID state electronics , *ANISOTROPY - Abstract
Abstract: The Goos–Hänchen shift at the surface of a uniaxially anisotropic left-handed material film is investigated, for the situation of that there is an arbitrary angle between the optical axis and the interface of the material. The analytical expressions of the Goos–Hänchen shifts are derived, for both cases of that the total reflection occurs and does not occur at the first interface. The sign of the Goos–Hänchen shifts in the two situations is analysed. The results show that the Goos–Hänchen shift of the reflected wave is the same as that of the transmitted one for the case that the total reflection does not occur at the first interface; the Goos–Hänchen shift of the transmitted wave oscillates as the thickness of the film is increased, and its overall tendency is increased; the Goos–Hänchen shift of the transmitted wave realizes its absolute maximum when the transmitted wave resonances, the absolute maximum is almost several 10 times of the wavelength of the incident wave; the Goos–Hänchen shift of the transmitted wave is significantly influenced by the incident angle and the angle between the optical axis and the interface. [Copyright &y& Elsevier]
- Published
- 2008
- Full Text
- View/download PDF
42. Grating effect in negative permeability meta-material
- Author
-
Cai, Xiaobing and Hu, Gengkai
- Subjects
- *
LIQUIDS , *PERMEABILITY , *POROSITY , *ADSORPTION (Chemistry) - Abstract
Abstract: Abnormal transmission is found in meta-material with negative permeability, this transmission is attributed to grating effect. A grating model with an effective negative permeability material is proposed, it is found that indeed the grating model can give a good prediction on the unusual transmission. [Copyright &y& Elsevier]
- Published
- 2008
- Full Text
- View/download PDF
43. Negative refraction and imaging beyond the diffraction limit by a two-dimensional left-handed metamaterial.
- Author
-
Ozbay, Ekmel and Aydin, Koray
- Subjects
NEGATIVE refraction ,OPTICAL diffraction ,METAMATERIALS ,PERMITTIVITY - Abstract
Abstract: We report our experimental results on two-dimensional left-handed metamaterials (LHM) exhibiting negative refraction and subwavelength imaging. Transmission and reflection spectra of LHM are studied and a left-handed transmission band is observed at the frequencies where both dielectric permittivity and magnetic permeability are negative. Impedance matching is verified both with the experiments and simulations. The two-dimensional LHM structure is verified to have a negative refractive index. We employed three different methods to observe negative refraction; refraction through prism-shaped LHM, beam shifting method, and phase shift experiments. We further demonstrated subwavelength imaging and resolution using LHM superlenses. The effect of thickness on the resolving power is investigated experimentally. [Copyright &y& Elsevier]
- Published
- 2008
- Full Text
- View/download PDF
44. Gap soliton of surface plasmon polaritons in left-handed material
- Author
-
Zhang, Yongliang, Zhang, Mingrui, and Jiang, Xunya
- Subjects
- *
VACUUM , *ELECTRIC discharges , *ULTRAHIGH vacuum , *VACUUM microbalances - Abstract
Abstract: We studied gap soliton of surface plasmon polaritons (SPPs) at an interface between vacuum and a Kerr nonlinear left-handed material (LHM). Applying multiple scale method, we derived the nonlinear coupled-mode equations for the gap soliton of SPPs. The linear gap is obtained and the bistable behavior of the transmissivity for the finite extend of the surface is presented. [Copyright &y& Elsevier]
- Published
- 2008
- Full Text
- View/download PDF
45. A periodic porous-nanostructured left-handed material slab at optical frequencies.
- Author
-
Chen, P.-Y. and Wu, S.-C.
- Subjects
- *
CONSTRUCTION slabs , *POROUS materials , *METALS , *REFRACTIVE index , *ELECTRIC fields , *ELECTROMAGNETIC waves , *OPTICAL communications - Abstract
We have proposed and theoretically investigated a left-handed material (LHM) slab composed of porous-nanostructed metal-dielectric-metal (MDM) networks for realizing negative refraction index at optical frequencies. In our design, whatever the polarization direction, provided that the electric field vector of incident EM wave is parallel to the metallic network, can “see” an equivalent LHM slab due to the symmetry and periodicity of the porous arrays. Another point needed to be highlighted is that by adjusting the periodicity of the porous arrays, a broad band of negative refraction index can be obtained. This shed the bright light on realizing negative refraction index for nanooptics and imaging applications. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 216–220, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23022 [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
- View/download PDF
46. Metamaterials for optical and radio communications
- Author
-
Kante, Boubacar, Ourir, Abdelwaheb, Burokur, Shah Nawaz, Gadot, Frédérique, and de Lustrac, André
- Subjects
- *
METAMATERIALS , *TELECOMMUNICATION systems , *ANTENNA arrays , *PERMITTIVITY , *PERMEABILITY , *ELECTRONICS - Abstract
Abstract: We present here two examples of metamaterials for applications in the telecoms domain. The first concerns the realization of an ultra compact directive electronically reconfigurable antenna. The second deals with an infrared left-handed metamaterial working under normal incidence. For the first application, we use a composite phase varying metamaterial. An adjustable resonance radiating frequency between 7.9 and 8.2 GHz is obtained and a drastic enhancement in the directivity of the antenna is observed for a cavity thickness as small as (0.5 mm!). Concerning the second application we present simulations and measurements of a metamaterial made of gold wires and C-shaped nanostructures on silicon at infrared wavelengths. Both plasmonic resonances occur at 1.7 and 4.2 μm, corresponding to a simultaneously negative permittivity and permeability. A simplified version of this metamaterial is realized in the microwave domain. This new metamaterial is characterized and the left-handed behavior is experimentally demonstrated. To cite this article: B. Kante et al., C. R. Physique 9 (2008). [Copyright &y& Elsevier]
- Published
- 2008
- Full Text
- View/download PDF
47. FOUR-WAVE MIXING IN LEFT-HANDED MATERIALS.
- Author
-
GAO, SHIMING and HE, SAILING
- Subjects
- *
MATERIALS , *NONLINEAR boundary value problems , *WAVELENGTHS , *ARBITRARY constants , *PARAMETER estimation - Abstract
The four-wave mixing (FWM) effect in a so-called left-handed material (LHM) with a third-order nonlinear response is studied. The theoretical models for the wavelength conversion (WC) and parametric amplification (PA) based on the FWM in the LHM are established when the signal falls in the frequency range of backward or forward wave. Analytical formulas for the WC efficiency and PA gain are derived. The influences of the pump powers, the phase mismatch, and the interaction length on the performances of the WC and PA are analyzed. The phase-match dependence of the performance is reduced by carefully controlling the pump powers. [ABSTRACT FROM AUTHOR]
- Published
- 2007
- Full Text
- View/download PDF
48. Preparation of substituted barium ferrite BaFe12− x (Ti0.5Co0.5) x O19 by citrate precursor method and compositional dependence of their magnetic properties
- Author
-
Koga, Nobuyoshi and Tsutaoka, Takanori
- Subjects
- *
BARIUM , *PERMEABILITY , *FERROMAGNETISM , *MAGNETIZATION - Abstract
Abstract: As a possible candidate for the left-handed metamaterial with negative permeability, a series of Ti, Co-substituted M-type barium hexaferrite BaFe12− x (Ti0.5Co0.5) x O19 (x=0, 1, 2, 3, 4 and 5) was prepared by citrate precursor method. The formation processes of the substituted barium hexaferrite compounds from the precursors were followed by the measurements of powder X-ray diffraction (XRD), Infrared absorption spectra (FT-IR), and thermogravimetry and differential thermal analysis (TG/DTA) coupled with mass spectroscopy (MS). In the case of the non-substituted sample, the formation of the barium hexaferrite is regulated by the thermal decomposition of BaCO3 and the solid-state reactions of BaO and Fe2O3 in the temperature range from 800 to 1100K. The formation temperature of the substituted BaFe12− x (Ti0.5Co0.5) x O19 is higher than that for the non-substituted sample and increases with the value of x, due to the effects of carbonate ions incorporated by the partial substitution of Fe3+ by (Ti0.5Co0.5)3+. On heating up to ca. 1200K, all the substituted samples transform into the magenetoplumbite phase as is the non-substituted sample. The compositional dependence of the magnetic properties of the substituted barium hexaferrite was investigated by the magnetization measurement. The decrease in the magnetic anisotropy was confirmed by the change in the magnetization curve and coercivity H C with the composition x. A negative permeability spectrum was observed in the BaFe9(Ti0.5Co0.5)3O19 in the frequency range from 2 to 4GHz. [Copyright &y& Elsevier]
- Published
- 2007
- Full Text
- View/download PDF
49. Optimal parameter relations to realize high-power transmission in planar waveguide filled with lossy left-handed material
- Author
-
Cheng, Qiang and Cui, Tie Jun
- Subjects
- *
POWER transmission , *WAVELENGTHS , *WAVEGUIDE filters , *INTEGRALS - Abstract
Abstract: In a planar waveguide filled with two-layered equal-thickness media, in which one is air and the other is a lossy left-handed medium (LHM) with the relative permittivity and permeability , we show rigorously that extremely high power densities can be generated and transmitted along the waveguide. In such a lossy super waveguide, the poles in the relevant integrals are complex, whose real parts represent the wavenumbers of guided modes propagating along the waveguide and imaginary parts denote the attenuations of guided modes. We find that optimal values of the retardation parameter exist once the loss in LHM is given to make the transmitted power be maximum. Compared with the conventional air-filled waveguide, at an observation point 10 wavelengths away from the source, the transmitted power density in the lossy super waveguide can be 10000 times larger even when the loss is as high as and the retardation is as large as . [Copyright &y& Elsevier]
- Published
- 2007
- Full Text
- View/download PDF
50. Experimental study of the hybridizing effect of different left-handed metamaterials
- Author
-
Zhang, Haifei, Huangfu, Jiangtao, Wang, Dongxing, Chen, Hongsheng, Peng, Tao, Ran, Lixin, and Kong, Jin Au
- Subjects
- *
RESONATORS , *METAMATERIALS , *COMPOSITE materials , *ELECTROMAGNETISM - Abstract
Abstract: We present the first study of the hybridizing effect of different left-handed metamaterials (LHM) based on S-shaped and Ω-shaped resonators. Three different cases of hybridizing are investigated, ten configurations of various hybrid ratio are simulated, fabricated and measured, and a series of different left-handed passbands is obtained, showing that the left-handed passband of the proposed hybrid structure can be controlled by tuning the hybrid ratio. The hybrid left-handed metamaterial proposed in this Letter has potential applications in LHM-based filters, couplers, antennas, etc. [Copyright &y& Elsevier]
- Published
- 2007
- Full Text
- View/download PDF
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