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Liu L.,CAS Shenzhen Institutes of Advanced Technology | Rozanov K.N.,Institute for Theoretical and Applied Electromagnetics | Abshinova M.,National University of Singapore
Applied Physics A: Materials Science and Processing | Year: 2013

Tunable electromagnetic properties (permeability and permittivity) of composites filled with glass-coated microwires under external magnetic field were investigated experimentally. The microwire composites have been measured with 7 mm coaxial airline fixture and vector network analyzer from 0.01 to 18 GHz. The ferromagnetic resonance may contribute to the tunability of permeability of microwire composites. The tunability of effective dielectric permittivity may be attributed to the magnetoimpedance effect. The microwire composites are promising candidates for smart or tunable applications at microwave frequency. © 2012 Springer-Verlag Berlin Heidelberg.


Fleger Y.,Bar - Ilan University | Rosenbluh M.,Bar - Ilan University | Strelniker Y.M.,Bar - Ilan University | Bergman D.J.,Tel Aviv University | Lagarkov A.N.,Institute for Theoretical and Applied Electromagnetics
European Physical Journal B | Year: 2011

The extinction spectrum of a dielectric film with periodic array of metallic islands of different shapes and different mutual distances was studied both theoretically and experimentally. It is shown, analytically, numerically and experimentally, that the positions of the surface plasmon resonances depend on the nano-structural details. We propose two ways of controlling plasmon resonance frequency: Changing the aspect ratio of the elliptical (or rectangular) islands and changing their mutual distances. A new analytical asymptotic approach for calculating the optical properties of such plasmonic systems is developed. The results of our analytical and numerical studies are in good qualitative agreement with experiment. © 2011 EDP Sciences, Societàna di Fisica, Springer-Verlag.


Lagarkov A.N.,Institute for Theoretical and Applied Electromagnetics | Kisel V.N.,Institute for Theoretical and Applied Electromagnetics | Sarychev A.K.,Institute for Theoretical and Applied Electromagnetics
Journal of the Optical Society of America B: Optical Physics | Year: 2010

Results of studies in the influence of losses on the superresolution achievability are presented. The studies involve modeling and realization of superresolution devices. It is found that rigorous electrodynamic models that are not based on homogenization of composites can be effectively used in modeling devices with metamaterials. The possibilities to compensate losses in near-optic metamaterials by means of active inclusions or active medium are discussed and the active material design is presented. Alternatively, what we believe to be new designs are suggested for applications where losses are desirable. © 2010 Optical Society of America.


Starostenko S.N.,Institute for Theoretical and Applied Electromagnetics | Rozanov K.N.,Institute for Theoretical and Applied Electromagnetics
IEEE Magnetics Letters | Year: 2015

A theoretical and experimental study of filling effect on the microwave constitutive parameters of a metamaterial with resonant inclusions is performed. The metamaterial is a planar anisotropic layer containing a regular array of coreless split ring inclusions and is considered to be a homogeneous medium. The electric and magnetic susceptibilities of the inclusions are measured and compared with predictions of the generalized Maxwell Garnett theory that accounts for the percolation threshold. The threshold for permittivity is calculated based on the structure of the sample and the sizes of the split rings. The electric interaction of the split rings is close to the dipole interaction of the metal disks. The magnetic interaction depends on the overlapping of ring-induced magnetic fields. When the overlap is negligible, the permeability is defined by the volume of a permeable prolate ellipsoid with magnetic moment equal to the moment induced by the ring. The flatter the split ring, the longer is the prolate ellipsoid and the higher is its volume compared to the volume of the ring inclusion itself. This approach allows the metamaterial constitutive parameters to be calculated based on the dimensions and filling factor of the inclusions, the same as in a powder-filled composite. © 2016 IEEE.


Starostenko S.N.,Institute for Theoretical and Applied Electromagnetics | Rozanov K.N.,Institute for Theoretical and Applied Electromagnetics
Journal of Magnetism and Magnetic Materials | Year: 2015

An analytic approach to calculate induced permeability of metamaterial filled with helix inclusions is developed. For an electrically small coil, the dynamic magnetization is determined by lumped inductance, capacitance, and resistance that are calculated from the coil design. The susceptibility of a coil is shown to be close to that of diamagnetic ellipsoid of the same elongation. Contrary to permeable particles in a composite, the coils screen each other thus decreasing the magnetic response of metamaterial compared to total response of comprised coils. The filling effect on magnetic spectrum of metamaterial is analyzed and verified by measurements for the case of identical coaxially placed coreless coils. The critical filling where magnetic response of metamaterial is maximal depends on coil shape and resistance. The coil-filled metamaterials may find applications as permeable EMI suppressors or microwave absorbers free of Snoek or Acher limitations on the high-frequency permeability, as well as of Curie limitation on the high-temperature magnetic performance. © 2014 Elsevier B.V.


Rozanov K.N.,Institute for Theoretical and Applied Electromagnetics | Koledintseva M.Y.,Missouri University of Science and Technology
IEEE International Symposium on Electromagnetic Compatibility | Year: 2013

Engineering of magnetic composites with high microwave permeability is important for EMC/EMI and other applications. One of the challenging problems is to determine constraints on the achievable high-frequency permeability of magnetic composites. The objective of the present paper is to analyze the data available from the literature on the microwave permeability constraints and derive a generalized constraint condition. It is well known that in many practical occasions the actual magnetic frequency dispersion curves differ from the Lorentzian behavior. For these cases, an integral form of the constraint may be useful. Possible applications of the integral constraint are discussed for the cases of large damping, pronounced effect of eddy currents, and inhomogeneous materials. It is shown that the derived constraint can be successfully used in these cases for both estimating microwave performance of devices containing magnetic materials and obtaining additional data on the magnetic structure of materials. © 2013 IEEE.


Baryshev A.V.,Toyohashi University of Technology | Baryshev A.V.,RAS Ioffe Physical - Technical Institute | Merzlikin A.M.,Toyohashi University of Technology | Merzlikin A.M.,Institute for Theoretical and Applied Electromagnetics | Inoue M.,Toyohashi University of Technology
Journal of Physics D: Applied Physics | Year: 2013

A one-dimensional photonic crystal with termination by a noble metal film - a plasmonic photonic-crystal slab - is theoretically analysed for its optical response at the variation of the dielectric permittivity of an analyte. A sharp attenuation peak associated with a 'noble metal-visualized' Bloch surface wave is observed due to plasmon absorption in the metal. We investigate the sensing performance of the slab and show that it is tolerant to the variation of probing conditions and the slab's structural parameters. As a consequence, the considered sensor exhibits an enhanced sensitivity and good robustness in comparison with conventional surface-plasmon and Bloch surface wave sensors. © 2013 IOP Publishing Ltd.


Baryshev A.V.,Toyohashi University of Technology | Baryshev A.V.,RAS Ioffe Physical - Technical Institute | Merzlikin A.M.,Institute for Theoretical and Applied Electromagnetics
Applied Optics | Year: 2014

The Bloch surface wave resonance (SWR) was visualized with the aid of plasmon absorption in a dielectric/metal/dielectric sandwich terminating a one-dimensional photonic crystal (PhC). An SWR peak in calculated spectra of such a plasmonic photonic crystal (PPhC) slab comprising a noble or base metal layer was demonstrated to be sensitive to a negligible variation of refractive index of a medium adjoining to the slab. The considered structure of PPhC slabs can be of practical importance because the metal layer is protected by a capping dielectric layer from contact with analytes and, consequently, from deterioration. We found that, in case of PPhC slabs, gold (the key element of the surface plasmon resonance-based biosensors) can be replaced by other metals. The PPhC-based sensors can be low-cost, reusable, and robust sensors having a sensitivity surpassing that of the known optical sensors. © 2014 Optical Society of America.


Ignatov A.I.,Institute for Theoretical and Applied Electromagnetics | Merzlikin A.M.,Institute for Theoretical and Applied Electromagnetics | Vinogradov A.P.,Institute for Theoretical and Applied Electromagnetics | Lisyansky A.A.,Queens College, City University of New York
Physical Review B - Condensed Matter and Materials Physics | Year: 2011

Light propagation in a random system of isotropic magnetodielectric layers is studied numerically and analytically. It is shown that if the values of permittivity and permeability are randomly distributed, whereas the characteristic impedance does not change throughout the system, the Lyapunov exponent (the inverse localization length) grows with the angle of incidence and does not depend on the polarization of the incident wave. This independence appears only on the ensemble averaging because in any specific realization the transmission coefficients for s- and p-polarized light are different. The numerical results confirm analytical analysis. © 2011 American Physical Society.


Rozanov K.N.,Institute for Theoretical and Applied Electromagnetics | Koledintseva M.Y.,Missouri University of Science and Technology
IEEE International Symposium on Electromagnetic Compatibility | Year: 2012

Electromagnetic materials applied to solve various EMC and EMI problems require adequate analytical description of their RF and microwave material parameters. This is necessary for numerical optimization of wideband electromagnetic performance of devices incorporating these materials. The paper discusses the shape of frequency dependences of microwave permeability in homogeneous materials and composites. The Lorentzian frequency dispersion law is shown to allow for rather accurate description of all types of magnetic loss peaks, including those related to the ferromagnetic resonance and the effect of eddy currents. To model wideband electromagnetic performance of composites, mixing laws are typically used. The problem is which mixing law is to be chosen to adequately describe a particular composite. The paper gives recommendations on how to make the choice of a proper mixing rule. © 2012 IEEE.

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