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TE guided modes at microwave frequencies in metal-left-handed material-ferrite waveguide structures are studied numerically. The effect of ferrite layer parameters on the dispersion properties of the waveguide structure is investigated in details. It is found that the modal index of the guided mode is negative as if the overall structure was left-handed material. A considerable effect of the gyromagnetic ferrite layer on the dispersion properties of the structure is observed. The power propagating in each layer is also evaluated. [ABSTRACT FROM AUTHOR]

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]

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]

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]

• 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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

The paper is concerned with the propagation characteristics of TE surface waves in a planar wave-guide structure of a lateral antiferromagnetic-non magnetic super lattices (LANS) film bounded by a nonlinear dielectric cover and a left-handed substrate (LHM). In LHM substrate both permittivity and magnetic permeability are negative in definite frequency range. We study nonlinear dispersion properties of the TE surface waves and illustrate the power flow variation with the wave index in three different cases, i.e., when both permittivity and magnetic permeability are negative, when permittivity is negative and permeability is positive, and when both permittivity and magnetic permeability are positive. In the first case, we found that surface waves are backward traveling and the wave power variation with the wave index shows bistability behavior. We also found that by increasing the film thickness the waves turn from forward to backward traveling in the second case. In the third case, surface waves are always forward traveling. [ABSTRACT FROM AUTHOR]

We will investigate the surface plasmon (SP) resonances of a dielectric-sandwiched metamaterial thin film. The parameters of the metamaterial are chose so that it has both negative $$\epsilon$$ and μ in visible frequency range. We use transfer matrix method to calculate the attenuated total reflection (ATR) spectra of the layered system to investigate the variation of SP resonances and the associated resonance strength. The results show that, for both p- and s-polarized incident lights, the plasmonic resonances can be manipulated by changing the thickness of the metamaterial. Otherwise, the plasmonic resonance strength for each SP mode can be tuned to become a maximum with proper slab thickness and light frequency for both polarized lights. [ABSTRACT FROM AUTHOR]

Abstract: On the basis of angular spectrum representation, a formalism describing paraxial beams propagating through an isotropic left-handed material (LHM) slab is presented. The treatment allows us to introduce the ideas of beam focusing and phase compensation by LHM slab. Because of the negative refractive index of LHM slab, the inverse Gouy phase shift and the negative Rayleigh length of paraxial Gaussian beam are proposed. It is shown that the phase difference caused by the Gouy phase shift in right-handed material (RHM) can be compensated by that caused by the inverse Gouy phase shift in LHM. If certain matching conditions are satisfied, the intensity and phase distributions at object plane can be completely reconstructed at the image plane. [Copyright &y& Elsevier]

Abstract: On the basis of Landau–Lifshitz–Gilbert (LLG) equation, an anomalous ferromagnetic resonance behavior is demonstrated in detail. Coupling between the magnetic moments produces a 3π/2 phase delay for one of the moments ferromagnetic resonance unusually, thus leads the sign of magnetic susceptibility to be opposite to that induced by the usual ferromagnetic resonance. Consequently, a left-handed material (LHM) may be formed near the low-frequency side of the resonance. Particularly, a LHM with negative value of real part of permeability only is predicted. [Copyright &y& Elsevier]

In this paper, we present a novel method to calculate the effective negative refractive index of a left-handed material (LHM)—a composite of split-ring resonators (SRRs) and thin wire structures. A LHM slab was first fabricated and then the measured transmission and reflection results were used to determine the LHM passband. To obtain the effective negative-refractive index, a microwave beam was obliquely launched to illuminate the slab for which a 2D spatial-field profile of the refracted beam outside the slab was obtained by scanning the lateral shifting of the field with respect to normal for a band of frequencies. A lateral shift of the refracted beam towards the same side of the incident beam for the LHM passband confirmed negative refraction in the LHM slab and the refractive index calculated for that frequency region was conclusively negative according to Snell's law. The presented method provides an alternate and efficient way to measure the effective refractive index of a LHM. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 593–596, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21417 [ABSTRACT FROM AUTHOR]

Abstract: Negative magnetic permeability of split ring resonator (SRR) is theoretically investigated in the visible light region. In our calculations, we considered the delay of the current inside the metal SRR in order to estimate the permeability of the SRR precisely. From the results, the silver SRR array with small capacitance exhibits negative permeability in all the visible range. The dependence of the permeability on the filling factor of the SRR elements is also discussed. [Copyright &y& Elsevier]

The Doppler effects for the reflected wave from moving media are systemically analyzed in this paper. The theoretical formula for the Doppler shift in left-handed material, which is described by Drude's dispersion model, is presented. This formula is examined by first-principles numerical experiments, which are in agreement with the theoretical results. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 47: 76–79, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21086 [ABSTRACT FROM AUTHOR]

Abstract: In this Letter, we study the properties of one-dimensional quasi-periodic photonic crystal containing left-handed material. In the light of the dispersion relation, we show that one-dimensional quasi-periodic photonic crystal can exhibit complete reflection at a given microwave frequency for all incident angles and both polarizations (s- and p-polarizations). The influence of left-handed material''s permittivity and permeability on the omnidirectional reflection is also discussed. We find that when is larger than , it is difficult to realize the omnidirectional reflection for p-polarization, on the contrary, it is difficult to realize the omnidirectional reflection for s-polarization when is larger than , which is expected to realize omnidirectional reflection in a certain frequency region. The effect of the left-handed material''s absorption on omnidirectional reflection is also investigated. [Copyright &y& Elsevier]

Using the equifrequency surfaces (EFS) to describe negative refractions in left-handed materials (LHMs) and photonic crystals (PCs), negative phase and negative group refractive indexes in LHMs were compared with positive phase and negative group refractive indexes in PCs. The refractive indexes in PCs were dependent on frequencies and incident angles of electromagnetic wave, while indexes in LHMs were constant in the left-handed region. Furthermore, the phase compensating effect resulting from the negative phase refractive index was addressed to distinguish the perfect lens made of LHMs from the superlens realized in the all angle negative refraction (AANR) region of PCs. [ABSTRACT FROM AUTHOR]

In this paper, we present an analysis of the dispersion properties for a left-handed material (LHM) using the 3D finite-difference time-domain (FDTD) method. We study the classic LHM structure composed of wire and split-ring resonators in a unit cell and calculate the resonant frequencies in order to produce the corresponding dispersion curve. The comparisons made between our numerical results and those previously published are in good agreement. In addition, through the incorporation of the Padé approximation with our FFT results, we reduce the computational time and enhance the results obtained. We anticipate that the development of such analysis tools for dispersion analysis will lead to an efficient way of characterizing LHMs and will facilitate the study of such metamaterial composites. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 45: 394–397, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20833 [ABSTRACT FROM AUTHOR]

Abstract: We investigate the possibility of preparing left-handed material in a layered alternated nonmagnetic/magnetic composite under different direction of incident electromagnetic wave at the microwave region. We calculate the effective refractive index of the layered composites and find that the effective refractive index varies as a function of the volume fraction of one component of the composite. Especially, within the certain volume fraction of component 1 (or 2) the effective refractive index can be negative at a finite frequency region. Moreover, we find that the direction of the incident electromagnetic wave affects the effective refractive index greatly. When the incident electric field is parallel to the laminations and the magnetic field is perpendicular to the laminations, the volume fraction of component 1 (or 2) range, which causes the effective refractive index to be negative, is relatively wider than that of the opposite case, but the absolute values of the negative refractive index are smaller than that of the opposite case. [Copyright &y& Elsevier]

Backward-wave (BW) materials that have simultaneously negative real parts of their electric permittivity and magnetic permeability can support waves where phase and power propagation occur in opposite directions. These materials were predicted to have many unusual electromagnetic properties, among them amplification of the near-field of a point source, which could lead to the perfect reconstruction of the source field in an image [J. Pendry, Phys. Rev. Left. vol. 85, pg. 3966, 2000]. Often systems containing BW materials are simulated using the finite-difference time-domain technique. We show that this technique suffers from a numerical artifact due to its staggered grid that makes its use in simulations involving BW materials problematic. The pseudospectral time-domain technique, on the other hand, uses a collocated grid and is free of this artifact It is also shown that when modeling the dispersive BW material, the linear frequency approximation method introduces error that affects the frequency of vanishing reflection, while the auxiliary differential equation, the Z-transform, and the bilinear frequency approximation method produce vanishing reflection at the correct frequency. The case of vanishing reflection is of particular interest for field reconstruction in imaging applications. [ABSTRACT FROM AUTHOR]

In this article, we present an experimental and numerical study of novel optical properties of two-dimensional dielectric photonic crystals (PCs) which exhibit negative refraction. We investigate two mechanisms which utilize the band structure of the PC to generate a negative effective index of refraction (neff<0) and demonstrate the negative refraction experimentally. To the isotropic extend of neff, different PC slab structures are employed to focus the radiation of a point source. It is shown experimentally that the PC can generate an image of the source with subwavelength resolution in the vicinity of the PC interface. Using a different PC, one can also obtain a far field focusing. In the latter case, we explicitly show the flat lens behavior of the structure. These examples indicate that PC-based lenses can surpass limitations of conventional lenses and lead to novel optics applications. [ABSTRACT FROM AUTHOR]