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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]

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]

A new leaky wave antenna based on channel guide filled with left-handed material (LHM), operating in evanescent surface mode of TM polarization, is presented for millimeter wave applications. A transverse equivalent network that yields a dispersion relation in closed form is employed to analyze the leakage characteristics of the antenna. Numerical results are presented for the phase and leakage constants of the antenna in terms of different geometric parameters and dielectric distributions. Besides, the frequency dependences of the leaky characteristics for the present antenna are given, from which the backward radiation is clearly demonstrated. [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]

Abstract: We report the true left-handed transmission of a composite metamaterial (CMM) consisting of periodically stacked split-ring resonator (SRR) and wire elements. The negative permeability (μ <0) gap is demonstrated explicitly by comparing SRR and closed-ring resonator structures. We confirm experimentally that the plasma cut-off frequency of the CMM is determined by the combined dielectric response of SRR and wire elements, and it is much lower than that of the wire-only medium. This is crucial to identify the left-handed transmission bands of the CMM. We further investigate the effect of intralayer and interlayer disorder on the transmission spectrum of CMM arising from misaligned fabrication and stacking of the SRR layers. We found that the intralayer disorder affects the μ <0 gap of SRRs and the left-handed transmission band of CMM significantly, whereas the SRR transmission is rather immune to interlayer disorder. [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]

We study the properties of left-handed materials (LHMs) with the precise help of Sommerfeld integrals. First we argue by energy conservation principles that LHM has to be a backward-wave material (BWM). Then we derive the equivalence of the loss and the Sommerfeld far-field radiation conditions for a BWM. Next, we solve the realistic Sommerfeld problem of a point source over an LHM half-space and an LHM slab. This analysis lends physical insight into the interaction of a point source field with an LHM, showing that super-resolution is possible with an LHM slab. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 42: 369–373, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20307 [ABSTRACT FROM AUTHOR]

Here, we analyze the transverse-magnetic (TM) wave interaction with a pair of slabs, one being an epsilon-negative (ENG) layer in which the real part of permittivity is assumed to be negative while its permeability has positive real part, and the other being a mu-negative (MNG) layer that has the real part of its permeability negative but its permittivity has positive real part. Although wave interaction with each slab by itself has predictable features, we show that the juxtaposition and pairing of such ENG and MNG slabs may, under certain conditions, lead to some unusual features, such as resonance, complete tunneling, zero reflection and transparency. The field distributions inside and outside such paired slabs are analyzed, and the Poynting vector distributions in such structures are studied. Using equivalent transmission-line models, we obtain the conditions for the resonance, complete tunneling and transparency, and we justify and explain the field behavior in these resonant paired structures. Salient features of the tunneling conditions, such as the roles of material parameters, slab thicknesses, dissipation, and angle of incidence are discussed. The analogy and correspondence between the ENG-MNG pair and the pair of a slab of conventional material juxtaposed with a "double-negative" medium is also discussed. Finally, a conceptual idea for a potential application of such a "matched" lossless ENG-MNG pair in "ideal" image displacement and image reconstruction is proposed. [ABSTRACT FROM AUTHOR]

Surface p- and s-polarized stationary waves propagating along the interface between left-handed electromagnetic meta-material with three types of conventional materials: dielectrics, metals, and magnetic media with negative magnetic permeability μ(ω) are studied. The constraints for the existence of surface modes are identified. It is shown that the frequency domains of existence for p- and s-modes do not overlap and they are quite different for different types of interfaces. The Poynting vector and the density of energy associated with surface mode are calculated. Depending on the system parameters either p- or s-surface mode has the time-averaged Poynting vector directed opposite to the mode phase velocity. [Copyright &y& Elsevier]

Gaussian beam propagation in structures containing meta-materials with negative permittivity and negative permeability is numerically studied by using a bidirectional wide-angle finite-difference beam propagation method. Illustrative and quantitative views are given for various anomalous behaviors, such as the negative angle of refraction, beam refocusing, arbitrarily thin distributed Bragg reflector, and negative lateral shift of the reflected beam from a grounded slab, by a Gaussian beam propagating in some meta-material structures. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 37: 292–296, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10898 [ABSTRACT FROM AUTHOR]

Abstract: Based on classical electromagnetic theory, characteristics of guided modes in a rectangular waveguide filled with a pair of single-negative layers are studied. The results show that only surface waves of TE mode can propagate in this peculiar waveguide, no TM mode in any forms can propagate in it. In addition, TE waveguide modes will be affected by permeability ratio ? 1/? 2 and dielectric layer thickness ratio P. Finally, from the electric field distribution of TE mode, we find the amplitude and location of the electric field can be adjusted by changing the thickness ratio P. [Copyright &y& Elsevier]

Abstract: We propose a polarization splitter (PS) based on the slow light effect in a three-layer waveguide that consists of left-handed material (LHM) and dielectric layers with no birefringence. Transverse electric (TE) and transverse magnetic (TM) waves can be split by the intrinsic configuration of permittivity and permeability of LHM and dielectric layers. Simulation results are given to discuss the influence of electromagnetic parameters on the properties of our PS, and the capture and release of TE or TM waves are also realized in our PS which provides a flexible method to modulate the switching of different polarization waves. [Copyright &y& Elsevier]

Abstract: We propose a coarse multiplexer–demultiplexer (MUX–DEMUX) for two ITU-T recommended channels based on a directional coupler (DC) with left-handed material (LHM), whose size can be controlled to a thickness less than 1mm. Our MUX–DEMUX can mix and separate two wavelength channels by use of LHM sandwiched between two RHM straight waveguides of a DC. Its operation is by setting the coupling length of one wavelength to be half of that of the other wavelength, which can be easily realized with quite short devices’ length due to the enhancement of the coupling efficiency caused by LHM. At last, the loss effect of LHM is considered. [Copyright &y& Elsevier]

Abstract: We realize tunable giant Goos–Hänchen (GH) shift by adjusting the applied electric field on electro-optic (EO) crystal in a prism–waveguide system in which surface plasmon resonance (SPR) is excited by left-handed material (LHM), and in such a way the giant GH shift can be modulated with high flexibility. Necessary theoretical analysis is given by stationary-phase theory and simulation results illustrate the high sensitivity of tunable giant GH shift which has potential applications in integrated optics, optical sensors and optical modulators. [Copyright &y& Elsevier]

Abstract: We construct a refractive index detection structure based on a prism–waveguide coupling system with double negative (DNG) material guiding layer, where surface plasmon resonance (SPR) is generated and the refractive index of lossless as well as lossy sample can be detected by the location of the incident light at which lateral shift peak appears. Simulation results show that when sample is lossy, more than one lateral shift peaks appear at different incident angle when other parameters are fixed once the intrinsic and radiative dampings satisfy the sufficient condition of equation for a large lateral shift. [Copyright &y& Elsevier]

Abstract: We propose a very compact electro-optical switch based on a directional coupler (DC) with left-handed material (LHM). The embedded LHM will significantly reduce the size of directional coupler, and by apply a proper voltage at the straight waveguide a switch of two channels is realized. Simulation results show that a electro-optical switch with a size of 134μm×5.74μm can be realized. [Copyright &y& Elsevier]

Resonator modes in two-dimensional laser cavities with curved end mirrors filled with a left-handed material were investigated numerically using the extended Fox-Li mode calculation method. The results reveal that the phase profile on the curved end mirrors of a left-handed cavity is inverted relative to that of a cavity filled with a right-handed material. Furthermore, we show that the phase on the end mirrors takes discrete values of zero and ± π under stable resonator conditions, while it varies continuously under unstable resonator conditions. The differences between stable and unstable resonators significantly alter the far-field patterns of the lowest-loss modes. [ABSTRACT FROM AUTHOR]

Abstract: A compact polarization splitter (PS) with left-handed material (LHM) sandwiched between two right-handed material (RHM) waveguides of a directional coupler (DC) is proposed. Its operation is by setting the coupling length of TM polarization be half that of TE polarization. Theoretic analysis exhibits that the PS with a very small size of 138.4μm×18.6μm can be realized due to the inclusion of LHM even when the RHM with small birefringence is used. [Copyright &y& Elsevier]

Abstract: A wave-absorber model with air/left-handed medium/right-handed medium/metal structure is proposed. The wave-absorption properties of the structure are theoretically analyzed and numerically simulated. The structure’s parameters are optimized employing a genetic algorithm. The results show that under the conditions of that the wave is normally incident and the structure parameters are well matched, the peak values of the reflectivity can be reduced, the absorbing bandwidth can be broaden and an average reflectance of −12dB can be realized in the frequency range from 0.4GHz to 10GHz. [Copyright &y& Elsevier]

A fiber with left-handed material as the core, and right-handed material as the cladding has been analyzed by using Maxwell's equations. A Helmholtz equation is obtained and solved. Thus, some characteristic equations are obtained and studied further. Some novel propagation characteristics in LHM fiber are obtained. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 1039–1041, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22335 [ABSTRACT FROM AUTHOR]

We report the effective complex permittivity and permeability of 1D planar left-handed transmission-line metamaterials. These metamaterials are formed on coplanar waveguide (CPW) with simultaneous load of series-capacitive and shunt-inductive elements in periodic intervals. By employing our self-calibrated method of moments (MoM), the effective permittivity and permeability of these 1D metamaterials are numerically derived to illustrate the propagating and evanescent guided-wave behaviors over a microwave frequency range. We demonstrate that, in a certain frequency band, the permittivity and permeability simultaneously become negative with zero imaginary parts, and the transmission phase of a finite-extent CPW metamaterial becomes negative, as exhibited by both simulation and measurement. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1050–1052, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21597 [ABSTRACT FROM AUTHOR]

We report free space, microwave measurements with varying incidence angle on a material that exhibits a negative index of refraction. The experiments measure the index of refraction directly, for normal incidence, on prisms with three different apex angles. Snell's Law and the measured index are then used to verify refraction for off-normal incidence. The metamaterials used to construct the prisms are comprised of parallel metallic layers of posts and either "Greek key" spiral or split ring resonators. Despite this highly anisotropic composition, the measured refractive index was found to be nearly constant for exit angles up to 52° off the normal to the prism hypotenuse. In addition to being the first free space experimental verification of Snell's Law off the optical axis for this type of metamaterial, the measurements prove that the common parallel plate structures of negative index metamaterials are not acting as guided wave media. [ABSTRACT FROM PUBLISHER]

Abstract: The purpose of this paper is to show that semiconductor nano-structures built from non-magnetic InAs/GaAs nano-rings can exhibit simultaneously negative effective permittivity and permeability over a certain optical frequency range. The structures are resonant and have this property near the edge of absorption of the nano-rings. This can be particularly interesting in the investigation of the challenging problem of development of left-handed composite materials in the optical range. [Copyright &y& Elsevier]

The perfectly matched layer (PML) absorbing boundary condition (ABC) is extended to truncate the boundary of left-handed materials in the Finite-Difference Time-Domain (FDTD) simulation. The uniaxial material parameters are given in the frequency domain, and discretized in the FDTD update procedure by means of the Z-Transform technique. The effectiveness of the PML is demonstrated by numerical results. [ABSTRACT FROM PUBLISHER]

Summary: On total reflection from a half-space filled with an isotropic, homogeneous, weakly dissipative, dielectric-magnetic medium with negative phase-velocity (NPV) characteristics, it is shown here that a linearly polarized beam can experience either a negative or a positive Goos-Hauml;nchen shift. The sign of the shift depends on the polarization state of the beam as well as on the signs of the real parts of the permittivity and the permeability of the NPV medium. [Copyright &y& Elsevier]