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General equation for directed Electromagnetic Pulse Propagation in 1D metamaterial: Projecting Operators Method  [PDF]
Dmitrii Ampilogov,Sergey Leble
Physics , 2015,
Abstract: We consider a boundary problem for 1D electrodynamics modeling of a pulse propagation in a metamaterial medium. We build and apply projecting operators to a Maxwell system in time domain that allows to split the linear propagation problem to directed waves for a material relations with general dispersion. Matrix elements of the projectors act as convolution integral operators. For a weak nonlinearity we generalize the linear results still for arbitrary dispersion and derive the system of interacting right/left waves with combined (hybrid) amplitudes. The result is specified for the popular metamaterial model with Drude formula for both permittivity and permeability coefficients. We also discuss and investigate stationary solutions of the system related to some boundary regimes.
Acoustic wave propagation in fluid metamaterial with solid inclusions  [PDF]
Ivan Lisenkov,Roman Popov,Sergey Nikitov
Physics , 2010, DOI: 10.1007/s00339-010-6232-9
Abstract: Acoustic waves propagation of in composite of water with embedded double-layered silicone resin/silver rods is considered. Approximate values of effective dynamical constitutive parameters are obtained. Frequency ranges of simultaneous negative constitutive parameters are found. Localized surface states on the interface between metamaterial and "normal" material are found. Doppler effect in metamaterial is considered. Presence of anomalous modes are shown.
Wave Propagation in Rectangular Waveguide Filled with Anisotropic Metamaterial
Hedi Sakli,Dhaou Bouchouicha,Taoufik Aguili
International Journal of Computer Science Issues , 2012,
Abstract: In this paper a rigorous analysis of the Transverse Operator Method (TOM) followed by the application of the Galerkin method, is developed for studying the propagation in a rectangular metal waveguide filled with anisotropic metamaterial. The wave equation and the dispersion relations for guided and evanescent modes in the guide are obtained and analyzed. The higher order modes are exploited. The numerical results are obtained and compared to theoretical predictions. Numerical examples show the validity of this method. Anisotropic metamaterials found important industrial applications such as circulators, isolators, phase shifters and antennas.
Below-Cutoff Propagation in Metamaterial-Lined Circular Waveguides  [PDF]
Justin G. Pollock,Ashwin K. Iyer
Physics , 2013, DOI: 10.1109/TMTT.2013.2274780
Abstract: This paper investigates the propagation characteristics of circular waveguides whose interior surface is coated with a thin metamaterial liner possessing dispersive, negative, and near-zero permittivity. A field analysis of this system produces the dispersion of complex modes, and reveals in detail intriguing phenomena such as backward-wave propagation below the unlined waveguide's fundamental-mode cutoff, resonant tunneling of power, field collimation, and miniaturization. It is shown how the waveguide geometry and metamaterial parameters may be selected to engineer the lined waveguide's spectral response. Theoretical dispersion and transmission results are closely validated by full-wave simulations.
Slow Light in Metamaterial Waveguides  [PDF]
Benjamin R. Lavoie
Physics , 2013,
Abstract: Metamaterials, which are materials engineered to possess novel optical properties, have been increasingly studied. The ability to fabricate metamaterials has sparked an interest in determining possible applications. We investigate using a metamaterial for boundary engineering in waveguides. A metamaterial-clad cylindrical waveguide is used to provide confinement for an optical signal, thereby increasing the local electromagnetic energy density. We show that metamaterial-clad waveguides have unique optical properties, including new modes, which we call hybrid modes. These modes have properties of both ordinary guided modes and surface plasmon-polariton modes. We show that for certain metamaterial parameters, the surface plasmon-polariton modes of a metamaterial-clad waveguide have less propagation loss than those of a metal-clad guide with the same permittivity. This low-loss mode is exploited for all-optical control of weak fields. Embedding three-level {\Lambda} atoms in the dielectric core of a metamaterial-clad waveguide allows the use of electromagnetically induced transparency to control an optical signal. Adjusting the pump field alters the group velocity of the signal, thereby controllably delaying pulses. Using the low-loss surface mode of a metamaterial-clad guide reduces losses by 20% over a metal cladding without sacrificing the group velocity reduction or confinement. In addition, we show that losses can be reduced by as much as 40% with sufficient reduction of the magnetic damping constant of the metamaterial. As this work aims for applications, practical considerations for fabricating and testing metamaterial-clad waveguides are discussed. An overview of the benefits and drawbacks for two different dielectric core materials is given. Also, a short discussion of other modes that could be used is given.
Active split-ring metamaterial slabs for magnetic resonance imaging  [PDF]
Marcos A. Lopez,Jose M. Algarin,Manuel J. Freire,Volker C. Behr,Peter M. Jakob,Ricardo Marques
Physics , 2011, DOI: 10.1063/1.3574916
Abstract: In this work, it is analyzed the ability of split-ring metamaterial slabs with zero/high permeability to reject/confine the radiofrequency magnetic field in magnetic resonance imaging systems. Using an homogenization procedure, split-ring slabs have been designed and fabricated to work in a 1.5T system. Active elements consisting of pairs of crossed diodes are inserted in the split-rings. With these elements, the permeability of the slabs can be automatically switched between a unity value when interacting with the strong excitation field of the transmitting body coil, and zero or high values when interacting with the weak field produced by protons in tissue. Experiments are shown for different configurations where these slabs can help to locally increase the signal-to-noise-ratio.
The Propagation and Cutoff Frequencies of the Rectangular Metallic Waveguide Partially Filled with Metamaterial Multilayer Slabs
Dan Zhang;Jian-Guo Ma
PIER M , 2009, DOI: 10.2528/PIERM09082701
Abstract: In this paper, the wave propagation and the cutoff frequencies of a rectangular metallic waveguide, partially filled the metamaterial multilayer slabs have been studied. The equations of the TMM method are not complex and the numerical examples show that we can easily obtain the characteristics of the metamaterial multilayer's rectangular waveguide satisfyingly. The cutoff frequencies of the metamaterial waveguide show very different characteristics compared with the usual waveguide.
Controlled analogue experiments on propagation of seismic electromagnetic signals
Huang Qinghua
Chinese Science Bulletin , 2005, DOI: 10.1360/982004-312
Abstract: This study presented a method of laboratory analogue experiments based on a geographical scaling model and a waveguide model to investigate the characteristics of the propagation of seismic electromagnetic signals in the crust and the atmosphere. Some controlled experiments were done to evaluate the possible influence on the experimental results from the background electromagnetic field, geographical conditions, boundary effects, the source of electromagnetic signals (position, magnitude, and frequency), and media conductivity. The reliability and the extensibility of the above analogue experimental method were also investigated. This study indicated that such kind of analogue experimental method provided an intuitionistic way of studying the propagation of seismic electromagnetic signals, which is one of the most difficult research topics in seismo-electromagnetism.
A Crescent Shaped Split Ring Resonator to Form a New Metamaterial
Nidal Abutahoun,Mohamed Ouda
International Journal of Engineering and Technology , 2012,
Abstract: This paper proposes a new planner metamaterial consisting of crescent shaped split ring resonator unit cells. The cell is composed of a crescent shaped strip over one face of a dielectric substrate, and an oblong over the second face. The cell is very thin and easy to fabricate. The transmission characteristics of the structure were obtained using High Frequency Structure Simulator (HFSS) commercial software by ANSOFT. Then the effective material properties were retrieved. All the transmission characteristics and material properties were plotted to show the material behavior with frequency. The new metamaterial provides a double negative refractive index over a specific frequency band.
Electromagnetic Wave Propagation Through a Slab Waveguide of Uniaxially Anisotropic Dispersive Metamaterial
Song-Hua Liu;Chang-Hong Liang;Wei Ding;Liang Chen;Wei-Tao Pan
PIER , 2007, DOI: 10.2528/PIER07071905
Abstract: The characteristics of the guided electromagnetic wave propagation through a slab waveguide of uniaxially anisotropic dispersive metamaterial are investigated. Taking the cold plasma media model with ω < ω < ω as an example,the mode classification established in terms of the operating angular frequency ω of the slab waveguide. The results indicate that the mode properties are closely dependent on the frequency. When ω < ω < ω there are infinite guided modes. It is also found that when ω < ω < ω,there may be multiple solutions of the propagating mode with imaginary transverse wave number in a slab waveguide with thickness less than a certain value.
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