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Wyszukujesz frazę "41.20.Jb" wg kryterium: Temat


Tytuł:
On Electromagnetic-Acoustic Analogies in Energetic Relations for Waves Interacting with Material Surfaces
Autorzy:
Dukata, A.
Kapelewski, J.
Powiązania:
https://bibliotekanauki.pl/articles/1811519.pdf
Data publikacji:
2008-12
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
41.20.Jb
Opis:
In the paper we consider propagation of a monochromatic surface electromagnetic field at the interface separating two semi-infinite media - a metamaterial (generally with complex permittivity and permeability) and a conventional dielectric medium. The metamaterial is treated as homogeneous and isotropic (it is so-called effective medium approximation). It is true for e.g. artificial metamaterials with negative dielectric permittivity and negative permeability in the microwave frequency range. The last materials are known as left handed and a conventional as right handed media. In this work the classical optical theorem is extended to the case of scattering of electromagnetic surface waves incident at the interface separating a left handed medium and a right handed dielectric medium. The analogous theorem is known in the scattering theory for elastic fields.
Źródło:
Acta Physica Polonica A; 2008, 114, 6A; A-69-A-73
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Polaritonic Microwave Waves of Inclined Incidence in Some Magnetodielectric Superlattices
Autorzy:
Kapelewski, J.
Powiązania:
https://bibliotekanauki.pl/articles/1417967.pdf
Data publikacji:
2012-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
41.20.Jb
Opis:
This paper concerns a theoretical study of microwave phonon-polaritons excited in a planar magneto-dielectric composite by a plane electromagnetic wave obliquely incident on its surface. The composite consists of alternately spaced piezoelectric and piezomagnetic layers having transverse isotropic properties for both electromagnetic and elastic parameters. Results include direction-dependent dispersion for phase velocity of phonon-polariton modes being excited by the incident electromagnetic wave in the superlattice in consideration here. A peculiar kind of coupling is proved to appear in the system treated, which do not exist in the case of electromagnetic waves propagating along principal symmetry axes. The paper concludes with a short review of available literature data on current and prospective applications of the microwave polaritons.
Źródło:
Acta Physica Polonica A; 2012, 122, 5; 833-836
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Material Analysis and Application for Radio Frequency Electromagnetic Wave Shielding
Autorzy:
Yener, S.
Cerezci, O.
Powiązania:
https://bibliotekanauki.pl/articles/1187407.pdf
Data publikacji:
2016-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
41.20.Gz
41.20.Jb
Opis:
Our environment is full of radio frequency (RF) electromagnetic radiation due to rapid progress of wireless communication technologies, which have many applications, such as base stations of mobile communication networks and wireless internet antennas. In the context of Electromagnetic Compatibility (EMC) discipline, the word shield is used to describe any sort of metal sheet or material capable of reflecting, refracting or absorbing electromagnetic radiation (EMR), which is custom manufactured for the target electronic device casing, in a way to intervene any radiation passing to and from the device. Examining of electromagnetic shielding effectiveness (SE) is an important part of not only ensuring electromagnetic compatibility and of protecting electrical and electronic equipment but also protection of human beings against electromagnetic energy exposure as well. In this study, after a brief introduction and review on electromagnetic shielding, material selection and their applications for an indoor environment protection against electromagnetic radiation are explained. Potential electromagnetic shielding values of fabrics found in the market have been analyzed and compared by considering various criteria and requirements. Experimental results show that around 20 dB shielding effectiveness values can be obtained using test fabrics for a typical indoor environment.
Źródło:
Acta Physica Polonica A; 2016, 129, 4; 635-638
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Solid State Plasma in the Pulse Modulated Magnetic Field
Autorzy:
Jankauskas, Z.
Barauskas, S.
Kvedaras, V.
Powiązania:
https://bibliotekanauki.pl/articles/1807893.pdf
Data publikacji:
2009-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
40.41.Cr
41.20.Jb
Opis:
Radio frequency (RF) magnetoplasmic waves known as helicons will propagate in solid-state plasma of semiconductors when a strong magnetic field is applied. Helicons have an exact analogy with an electromagnetic whistler wave which is frequently propagated in the low density plasma of the Earth ionosphere. In our experiments the modulated magnetic field is being used for excitation of helicons. It is shown that in the case of pulse modulated field along with the RF helicon waves the transient cyclotron frequency oscillations exist in the semiconductor plasma. For observation of the cyclotron radiation frequency $ω_c$ the modulation depth about one percent is sufficient. The measurement of $ω_c$ provides an opportunity to determine the masses of electrons and holes in solid-state plasma of semiconductors. In already existing method the absorption of electromagnetic radiation on the cyclotron frequency is being used. For this case it is necessary to have an external infrared generator. In our method the cyclotron radiation is being generated by electrons (or holes) directly and additional external excitation is not needed.
Źródło:
Acta Physica Polonica A; 2009, 115, 6; 1025-1027
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Negative Refraction as a Source of Some Pedagogical Problems
Autorzy:
Veselago, V.
Powiązania:
https://bibliotekanauki.pl/articles/1814051.pdf
Data publikacji:
2007-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.20.Ci
41.20.Jb
Opis:
The appearance of material with negative values of dielectric and magnetic permeabilities ε and μ and with negative index of refraction n forces to revise the accustomed forms of some well-known formulae of electrodynamics. This is connected with fact, that these correlations in repressing majority of sources is written in tacit suggestion that magnetic permeability of most of materials is μ=1, factor of refraction n=ε and is undoubtedly executed the correlation n > 0. Such approach could be named as "nonmagnetic". However, if n <0, this nonmagnetic approach can bring very hard mistakes.
Źródło:
Acta Physica Polonica A; 2007, 112, 5; 777-781
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Acousto-Electromagnetic Analogies in Diffraction Phenomena Occurring in the Semi-Infinite Cylindrical Waveguide
Autorzy:
Snakowska, A.
Powiązania:
https://bibliotekanauki.pl/articles/1807756.pdf
Data publikacji:
2009-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
41.20.Jb
43.20.Wd
Opis:
The paper presents analogies between acoustic and electromagnetic wave field occurring in limited areas, such as waveguides, when electromagnetic waves are not purely transversal. The acousto-electromagnetic analogies exist in structures such as plane, rectangular or cylindrical infinite waveguides, if the fields are analysed by means of potentials - the velocity potential for sound waves and the Hertz potentials for electromagnetic waves. It has been demonstrated why these analogies between the potentials representing solutions of the wave equation with adequate boundary conditions and expressed as sums of admissible duct modes do fail, in general, for the semi-infinite cylindrical duct, and why they remain valid when the propagating electromagnetic mode is axisymmetric.
Źródło:
Acta Physica Polonica A; 2009, 116, 3; 410-413
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
TE Surface Waves in a Plasma Sandwich Structure
Autorzy:
Shaikh, M.
Zamir, B.
Ali, R.
Powiązania:
https://bibliotekanauki.pl/articles/1189881.pdf
Data publikacji:
2015-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
41.20.Jb
84.40.Az
Opis:
Transverse electric surface waves are analyzed in a plasma medium bounded by a left-handed material. A dispersion relation is obtained by applying the boundary conditions for the tangential field components. Numerical investigations show the dependence of effective wave index on the propagation frequency for different thicknesses and number densities of the plasma medium and also for different values of the filling factor of left-handed material.
Źródło:
Acta Physica Polonica A; 2015, 127, 6; 1625-1629
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Consequences of Unit Cell Design in Metamaterial Perfect Absorbers
Autorzy:
Bagci, F.
Akaoglu, B.
Powiązania:
https://bibliotekanauki.pl/articles/1398784.pdf
Data publikacji:
2016-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
81.05.Xj
41.20.Jb
Opis:
Metamaterials are a new class of composite materials with unusual properties that allow controlling of electromagnetic waves by properly engineering the response functions, which are not observed in constituent materials. However, since absorption of metamaterials is mainly based on electromagnetic resonances, the operating bandwidth is relatively narrow. Utilization of more than a single metallic structure with different geometrical parameters in each unit cell is a common way of accomplishing multiple band and/or broadband absorption. There are two usual approaches for this purpose: (a) multilayer unit cell design where metallic structures on dielectric substrate are stacked one on top of the other; (b) side by side unit cell design where metallic structures are distributed on a dielectric substrate. However, to the best of our knowledge, these two different approaches are not comparatively investigated. In this study, we propose metamaterial-based perfect absorbers with two different unit cell designs and simulate transmittances, reflectances and absorbances for each design by a commercial electromagnetic solver, CST Microwave Studio. It is found that each design has its own advantages in terms of device thickness, absorption bandwidth and angular dependence, which might be severely important for particular purposes.
Źródło:
Acta Physica Polonica A; 2016, 129, 4; 792-796
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Yearly, Seasonal and Daily Variations of Radio Refractivity
Autorzy:
Žilinskas, M.
Tamošiūnas, S.
Tamošiūnaitė, M.
Tamošiūnienė, M.
Powiązania:
https://bibliotekanauki.pl/articles/1505233.pdf
Data publikacji:
2011-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
84.40.-x
41.20.Jb
Opis:
Yearly, seasonal and daily variations of radio refractivity have been analyzed. The method proposed in the recommendation of International Telecommunication Union ITU has been used. The local meteorological data have been used in calculation of radio refractivity. The highest values of the radio refractivity have been observed in Klaipėda (in Seacoast) in the year 2009. In July, the values of the radio refractivity were highest in all localities investigated here and over all the time of the day in the year 2009. In the continental part of Lithuania (in Vilnius and Kaunas), analysis of radio refractivity has been made by using the meteorological data of longer period (starting from April 2005 up to July 2010). Five-year meteorological data collected in February, April, July and October have been used. It was obtained that the values of refractivity in the year 2010 are much higher than ones obtained in all the years of the period investigated here.
Źródło:
Acta Physica Polonica A; 2011, 119, 4; 533-536
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An Insight into Coherent Backscattering Evaluation Techniques of Prospective Use in High Frequency Polarimetric Radar Image Processing
Autorzy:
Kapelewski, J.
Powiązania:
https://bibliotekanauki.pl/articles/1506794.pdf
Data publikacji:
2010-12
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
41.20.Jb
03.50.De
Opis:
Coherence in multiple scattering is important as it applies to imaging and detection of object in multiple scattering environments. These phenomena may also be used to investigate images of objects obscured by them. The scattering observations using very rough surfaces can provide useful insight into their statistic as they lie outside the range of validity of the standard theories. Recently, there has been growing interest in the phenomenon of backscattering enhancement in the reflection of electromagnetic waves of mm wave range from both atmospheric hydrometeors (rain, snow and precipitation) as well as very rough surfaces (including that of sea and terrain sea). Strong backscattering enhancement of mm waves incident at different incident angles, both in the TE and TM polarizations, was observed experimentally. In the paper a short description of specific techniques used for treating image processing of strongly irregular media is shortly presented. An emphasis is placed on the phenomena of interest in advanced polarimetric radar especially in mm wave range.
Źródło:
Acta Physica Polonica A; 2010, 118, 6; 1161-1167
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Determination of Electromagnetic Emitter Position from Passive Radar Bearings as Linear Least Squares Problem
Autorzy:
Kawalec, A.
Kojdecki, M.
Wajszczyk, B.
Powiązania:
https://bibliotekanauki.pl/articles/1506796.pdf
Data publikacji:
2010-12
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
41.20.Jb
03.50.De
Opis:
Mathematical formulation of an inverse problem of radiolocation is discussed. Determination of electromagnetic emitter position from passive radar bearings is transformed into a linear least squares problem and equivalent system of normal equations. Eventually spatial localisation of emitter is reduced to solving system of linear algebraic equations with entries of coefficient matrix and free term depending on bearings in a nonlinear way. Regularisation algorithm is proposed.
Źródło:
Acta Physica Polonica A; 2010, 118, 6; 1171-1173
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Exact Phase and its Eikonal Approximation for Class of Reflectionless Index Profiles
Autorzy:
Sharma, S. K.
Ghosh, G.
Powiązania:
https://bibliotekanauki.pl/articles/1963260.pdf
Data publikacji:
1997-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
42.25.Fx
41.20.Jb
Opis:
We examine the problem of transmission of electromagnetic waves in a multiparameter reflectionless dielectric. It is shown that it is possible to obtain an analytic form for the phase of the exact transmission amplitude. In the high frequency limit the exact result is found to lead to the eikonal approximation. Interestingly, the high frequency limit and long-range approximation required for the validity of the eikonal approximation are not independent here.
Źródło:
Acta Physica Polonica A; 1997, 91, 3; 555-561
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Numerical Synthesis of a Radar Signal Having Required Autocorrelation Function
Autorzy:
Leśnik, Cz.
Kawalec, A.
Szugajew, M.
Powiązania:
https://bibliotekanauki.pl/articles/1506803.pdf
Data publikacji:
2010-12
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
41.20.Jb
03.50.De
Opis:
This paper presents the problem of synthesis of signals modulated in frequency with autocorrelation function that implements an optimal approximation to a given autocorrelation function. After theoretical introduction an algorithm of frequency modulated signal synthesis is presented. Simulation results made in Matlab are presented in the last section.
Źródło:
Acta Physica Polonica A; 2010, 118, 6; 1194-1198
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Investigation of Electromagnetic Wave Absorber Based on Carbon Fiber Reinforced Aerated Concrete Using Time-Domain Method
Autorzy:
Laukaitis, A.
Sinica, M.
Balevičius, S.
Levitas, B.
Powiązania:
https://bibliotekanauki.pl/articles/1813404.pdf
Data publikacji:
2008-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
41.20.Jb
81.05.Uw
Opis:
The electromagnetic wave absorbers prepared from autoclaved aerated concrete containing carbon fibers as additions in the shape of slabs with pyramids cut on one plane of these slabs were tested using dc microwave source and the time-domain method. It was demonstrated that autoclaved aerated concrete allows one to fabricate electromagnetic wave absorbers which have a reflection coefficient up to -30 dB in the frequency range from 2 GHz to 18 GHz.
Źródło:
Acta Physica Polonica A; 2008, 113, 3; 1047-1050
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Sharp-rejection, wide and deep stopband low pass filter design using open stubs and DGS patterns
Autorzy:
Challal, M.
Boulakroune, M.
Powiązania:
https://bibliotekanauki.pl/articles/1061519.pdf
Data publikacji:
2016-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
41.20.-q
41.20.Jb
11.10.-z
Opis:
A sharp rejection, wide and deep stopband microstrip low pass filter is investigated in this paper. The proposed low pass filter is composed of three defected ground structure patterns and four open stubs. Simulated results verify that the filter has a sharpness factor of 0.9, a low insertion loss of 0.65 and a return loss less than 15 dB. Moreover, a wide stopband at 20 dB rejection ranging from 4.55 GHz to 11.62 GHz is accomplished. The filter presented in this work was compared with the previous works completed on low pass filter with sharp rejection. It has shown that the filter provides good performances in terms of sharp rejection, wide and deep rejection band and small passband insertion loss compared to those reported in the literatures.
Źródło:
Acta Physica Polonica A; 2016, 130, 1; 9-10
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Imperfect Cloaking Devices Based on Metamaterials
Autorzy:
Isić, G.
Gajić, R.
Novaković, B.
Popović, Z. V.
Hingerl, K.
Powiązania:
https://bibliotekanauki.pl/articles/2047887.pdf
Data publikacji:
2007-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
41.20.Jb
42.25.Fx
78.20.Ci
Opis:
Cloaking devices designed using the coordinate transform approach were shown to be realizable, at least in principle, within the realm of electromagnetic metamaterials. In this paper we investigate the strictness of conditions imposed on the parameters of metamaterial cloaks by calculating the degree of wave scattering when those parameters have variations with respect to theoretically ideal values. A simple idea is used to obtain analytic results for the case of the nonideal two-dimensional cloaking cylinder. Also, results of realistic finite element simulations of the Helmholtz equation are presented and it is found that they are in excellent agreement with the analytic results.
Źródło:
Acta Physica Polonica A; 2007, 112, 5; 1083-1088
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effects of Loss Factor on Plane Wave Propagation through a Left-Handed Material Slab
Autorzy:
Sabah, C.
Powiązania:
https://bibliotekanauki.pl/articles/1812347.pdf
Data publikacji:
2008-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
04.30.Nk
41.20.Jb
78.20.Ci
Opis:
This article presents a theoretical and numerical discussion of the reflection and transmission analysis through a lossy left-handed material slab embedded between two semi-infinite dielectric media. The properties of the lossy left-handed material are given in detail and the required equations for the electromagnetic plane wave propagation are derived to solve the problem. The main important contribution of this article is the characterization of left-handed material that is different from its counterpart known in the literature. After introducing the left-handed material slab, the analytical solution is found for the powers carried by an electromagnetic wave. Then, the reflected, the transmitted, and the loss power are computed in terms of the incidence angle, the frequency, and the slab thickness in the numerical results with the emphasis on the loss factor.
Źródło:
Acta Physica Polonica A; 2008, 113, 6; 1589-1597
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Coupled Waves in Two-Phase Periodic Planar Multilayers
Autorzy:
Kapelewski, J.
Powiązania:
https://bibliotekanauki.pl/articles/1493229.pdf
Data publikacji:
2011-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
41.20.Jb
43.20.Mv
03.50.De
Opis:
In the paper a consequently dynamic model approach to the magnetoelectric coupling is proposed. As opposed to the static case the approach includes both the elastic equation of motion and the full set of the Maxwell equations for effective composite medium. The analytical treatment is performed from two layers of $\infty_m$ symmetry and results in closed relations for propagation characteristics of coupled elasto-electrodynamic waves for millimeter-length range.
Źródło:
Acta Physica Polonica A; 2011, 120, 4; 647-650
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Electromagnetic Wave Behaviour in Uniaxial Magnetodielectric Media of 1+1>2 Type
Autorzy:
Kapelewski, J.
Dukata, A.
Powiązania:
https://bibliotekanauki.pl/articles/1807729.pdf
Data publikacji:
2009-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
41.20.Jb
43.20.Mv
03.50.De
Opis:
In the paper a phenomenological approach is proposed to polarized electromagnetic wave propagation in magnetodielectric media, composed of piezoelectric and magnetostrictive anisotropic monolayers. The composite materials consisting of a system of such bimorph films have recently attracted much interest, because they can exhibit a much stronger magnetoelectric effect in a wide temperature range than the single phase multiferroic materials. In the paper dispersion equations given in a common form for both TE and TM modes are derived for long wave approximation. The equations can be of use in evaluation of directional dependence for particular polarizations, which is of particular interest in designing substrate for miniaturized polarimetric antenna, especially useful for modern synthetic aperture radar systems.
Źródło:
Acta Physica Polonica A; 2009, 116, 3; 331-334
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mechanisms of Gap Solitons Formation in Periodic Ferromagnetic Structures
Autorzy:
Morozova, M.
Nikitov, S.
Sharaevskii, Yu.
Sheshukova, S.
Powiązania:
https://bibliotekanauki.pl/articles/1427528.pdf
Data publikacji:
2012-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.40.Gb
75.70.Ak
41.20.Jb
Opis:
The features of envelope soliton formation in one-dimensional periodic ferromagnetic structure were considered. The model based on the coupled nonlinear Schrödinger equations was used for investigation. The parameter space showing the region in which solitons similar to the Bragg solitons with different features can form was calculated. The mechanisms of the formation of the solitons localized on the limited length of the structure were considered.
Źródło:
Acta Physica Polonica A; 2012, 121, 5-6; 1172-1175
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dispersion of Bloch Modes in a Multilayer Structure with Alternating Left-Handed and Right-Handed Materials
Autorzy:
Vukovic, S.
Aleksic, N. B.
Timotijevic, D. V.
Powiązania:
https://bibliotekanauki.pl/articles/2047883.pdf
Data publikacji:
2007-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
41.20.Jb
78.66.Fd
78.68.+m
Opis:
We study all-evanescent eigenmodes of a one-dimensional infinite periodic structure with alternating left-handed and right-handed materials that propagate perpendicularly to the surface or guided eigenmodes. Investigation of dispersion properties of such Bloch modes is shown to be crucial for understanding of an efficient radiation energy transport across the periodic multilayer structure. Frequency pass bands and gaps are found as a function of the two orthogonal wave vectors: the Bloch wave vector k$\text{}_{B}$ and the surface wave vector k$\text{}_{S}$. We demonstrate that pass bands of both TE- and TM-polarizations can exist and, under certain conditions, may overlap.
Źródło:
Acta Physica Polonica A; 2007, 112, 5; 1061-1066
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Confined Metamaterial Structures Based on Coordinate Transformations
Autorzy:
Vasić, B.
Gajić, R.
Isić, G.
Hingerl, K.
Powiązania:
https://bibliotekanauki.pl/articles/1807844.pdf
Data publikacji:
2009-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
03.50.De
41.20.Jb
42.70.-a
Opis:
We apply transformation optics to structures in which the electromagnetic field is confined by highly conducting coatings. The possibility of changing the field propagation direction without perturbation is demonstrated on the example of a waveguide bend. Using this approach it is also possible to reshape a confined structure in order to meet certain external requirements and to redistribute a field in order to obtain desired field distribution. The structure implementation implies replacing a part of given confined structure with a metamaterial designed using the technique of transformation optics. Simplification of structure realization based on using reduced set of material parameters is examined. Our theoretical considerations are confirmed by full wave finite element simulations of a waveguide bend.
Źródło:
Acta Physica Polonica A; 2009, 116, 1; 96-98
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mode Conversion in SiO₂/ZrO₂ Layer Doped with Magnetic CoFe₂O₄ Nanoparticles
Autorzy:
Bouras, M.
Hocini, A.
Powiązania:
https://bibliotekanauki.pl/articles/1401325.pdf
Data publikacji:
2015-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
04.30.Nk
41.20.Jb
92.60.Ta
Opis:
This paper describes the TE-TM mode conversion in a magneto-optical layer made by a SiO₂/ZrO₂ layer doped with magnetic CoFe₂O₄ nanoparticles. The mode conversion is caused by the Faraday rotation if the magnetization is aligned along the z-axis, parallel to mode propagation. The properties of this phenomenon are simulated using the full-vectorial beam propagation method (BPM). The simulation results show clearly the influence of two parameters in such devices, the first one is the off-diagonal component of tensor that enhances the rotation and the second one, the imaginary diagonal tensor (parameters K ) which makes it suffering from absorption. This result of simulation is an important step to achieve a monolithic integration of optical isolators.
Źródło:
Acta Physica Polonica A; 2015, 127, 4; 1191-1194
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimization of Directional Antennas in Two-Dimensional Artificial Dielectrics
Autorzy:
Janowicz, M.
Rusek, M.
Orłowski, A.
Powiązania:
https://bibliotekanauki.pl/articles/2037143.pdf
Data publikacji:
2004-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
41.20.Jb
84.40.Ba
42.25.Bs
Opis:
We investigate numerically the problem of optimization of directional characteristics of dipole antennas located inside, or in the vicinity of, photonic crystals or more general artificial dielectrics, made of very thin perfectly conducting wires. We concentrate on two-dimensional propagation. Simulated annealing is used to find the distribution of wires which optimizes the directional pattern. It is demonstrated that high directivity can be obtained for systems containing a very small number of elements provided that the size and shape of the unit cell as well as the position of the radiating source with respect to the crystal are optimized. Building up of the radiation pattern is also illustrated with the help of the wave-optical rays.
Źródło:
Acta Physica Polonica A; 2004, 105, 3; 263-278
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Frequency stop band in an air-voided ZnO photonic crystal: A dispersion diagram based design
Autorzy:
Chaturvedi, V.
Kumar Roy, M.
Powiązania:
https://bibliotekanauki.pl/articles/1075558.pdf
Data publikacji:
2016-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
01.65.+g
01.70.+w
41.20.Jb
78.20.-e
Opis:
Electromagnetic excitation, inside small volumes, results in perturbations which play an important role in the validation of theoretical formulations. Efforts to catch a glimpse of the action inside of the small space, can aid better thin film designs. In the non-linear anisotropic regime the results of such interactions provide important insights into the bulk level behavior of matter. Using this approach, a zinc oxide (ZnO) based photonic crystal is designed with spherical air voids. A Gaussian continuous wave excitation of the refractive index contrast (ZnO=1.9 and Air =1) photon waveguide generated thus, is characterized for the redistribution of electromagnetic field. When, centered at a specific wavelength (1.9 μ m), the graph of the frequencies that can exist inside the crystal, is plotted against the limited k-space vector. The dispersion diagram that emerges shows a band of frequency states that cannot exist inside such a design. Physically this constitutes a k-space which is devoid of any detectable disturbances. Crystallographically, the reduced Brilluoin zone can be used to make a thin layer of ZnO that can act as a frequency stop layer, in a real multilayered photoelectric device.
Źródło:
Acta Physica Polonica A; 2016, 130, 3; 683-687
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł

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