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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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

By using the method of Finite Difference Time Domain (FDTD) and the technology of Compute Unified Device Architecture (CUDA), the propagation characteristics of electromagnetic waves in Left‐Handed Materials (LHM) have been studied in this paper. The LHM slab was matched with the free space and the secondary focusing phenomenon of LHM was simulated. Compared with the serial FDTD program, our work showed that this method had a high accuracy. The phase compensation effect and the inverse Snell effect of LHM were also discussed by using the parallel FDTD method based on CUDA, which further proved that our results were consistent with the theoretical study. By comparing the calculation time of traditional FDTD program with that of the CUDA based parallel FDTD program, we conclude that the latter is more efficient than the former. This parallel method can be used as a more efficient way to study LHM. [ABSTRACT FROM AUTHOR]

A compact ring resonator using a negative-refractive-index microstrip line is presented. It is demonstrated that the ring structure resonates even with an inner diameter of zero. The total circumference of the proposed resonator is reduced by 84%, as compared to a conventional ring resonator at 1.2 GHz. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 45: 294–295, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20799 [ABSTRACT FROM AUTHOR]