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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]

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 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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]