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1
Content available remote Properties of chirped periodic layered medium with metamaterial layers
EN
Purpose: The purpose of the article was to investigate the absorption and reflectance properties of chirped periodic layered medium with metamaterial layers. Design/methodology/approach: The use of the algorithm TMM (Transfer Matrix Method) allows to determine the absorption and reflectance for the quasi one-dimensional multilayer structures. Can be analysed structure constructed with RHM (right-handed materials) and LHM (left-handed materials) with layers of any thickness and arranged in any way. It is possible to analyse lossy dispersive materials. Findings: In all the cases studied linear shift in the peaks with an increase in the k coefficient was observed. In all cases there was a shift to higher wavelengths. Noted an increase in the intensity and broadening half-width of the peaks. Research limitations/implications: The simulation was carried out only for the binary structure in the visible light range. Practical implications: Computer simulations allow us to design material with specified properties at a lower cost. The use of chirped periodic layered media allows to shift and broadening of the peak in the required range of work for mirrors or filter. Originality/value: Absorption and reflectance for chirped periodic layered systems using metamaterials layers have not yet been thoroughly investigated. Research can contribute to the implementation of mirrors with specific nonlinear properties.
2
Content available remote Transmission and photonic band gaps in Fibonacci superlattices
EN
Purpose: The purpose of the article was to broaden the knowledge about the behavior of Fibonacci superlattices as filters electromagnetic waves. Design/methodology/approach: Simulations of multi-layer systems is usually carried out by using two complementary methods. The first, matrix method which allows the study of the properties of structures using transmission maps and the second method used is the Finite-Difference Time Domain (FDTD) algorithm allows on the study of electromagnetic wave propagation in the structure. Findings: It can be seen that the lighting of the filter with monochromatic light in the wavelength range of the band gap filter at the output causes propagation of low intensity in the range other than the wavelength of the incident beam. Research limitations/implications: The simulation was not considered the impact of losses in the material. Practical implications: Present clear differences depending on the polarization allow the use of superlattices as polarizers for specific ranges of wavelengths and angles of incidence. Originality/value: Fibonacci superlattices have been pre-tested in. The purpose of the article was to broaden the knowledge about the behavior of these structures as filters electromagnetic waves with a wavelength range from the near infrared, the effect of the material surrounding the transmission and increasing knowledge of the formation of band gaps.
3
Content available remote The influence of extinction coefficient on transmission in binary multilayer
EN
Purpose: The influence of the extinction coefficient for transmission, reflectance and absorption in multilayer binary. Reps cluster was equal to 7 It was built of two types of materials. First was a NaCl equivalent with a refractive index described by nA=1.544-ik , and as second was GaAs lossless metamaterial equivalent Design/methodology/approach: Research was carried out using the map of: transmitting, reflectance and absorption of the electromagnetic wave. Maps determined using the matrix method. Findings: It is shown that the higher the extinction coefficient, which is responsible for the absorption of electromagnetic waves, decreases the transmittance and reflectance of the multilayer system at the same time increasing its absorption. Research limitations/implications: Would be a reasonable correlation between the results of the transmission, reflectance and absorption obtained using numerical methods with with experiment. Practical implications: Taking into account the extinction coefficient allows for a better representation of the real multilayer structures. Quasi one-dimensional superlattices can be used as filters or multiplexers electromagnetic waves. Originality/value: In the literature the most frequently analyzed lossless structure. Taking into account the extinction coefficient allows for better study the properties of the tested materials.
4
Content available remote Transmission in combination of structures
EN
Purpose: The paper investigated the effect of the combination of two structures on the transmission of electromagnetic waves as a multilayer filter. Examined how the combination of two structures affect the properties of the filter. As a component materials of structures used both right-handed material (RHM) and left-handed (LHM). Design/methodology/approach: Analysis was performed using a matrix method for calculating the superlattice transmission. The influence of combination of two types of multilayer systems: periodic (binary superlattice) and aperiodic (Severin’s and Thue-Morse’s superlattices). Findings: Studies have shown the structure of the transmission band of the structures, which is dependent on the polarization of the incident wave. Combination of various structures are not commutative, and therefore their transmission maps are not equal. Research limitations/implications: The structures analyzed in the work consisted of a lossless material, isotropic and non-dispersive. An important analysis would be lossy dispersive materials. You should also examine the impact would have a separating layer structure and the influence of defects on transmission properties of superlattices. Practical implications: The test structures may be used as filters of electromagnetic radiation. Placing the filter characteristics of the two structures allows pre-filtering an electromagnetic wave, in order to obtain a structure suitable for applications. Originality/value: The paper shows how combination of two periodic and aperiodic structures affect the propagation of electromagnetic waves in a multi-layered system. The analysis was based on the determination of unpolarized transmission maps for complex structures.
5
Content available remote The effect of polarization plane rotation on binary superlattice transmission
EN
Purpose: The purpose of this article is to examine what influence on the transmission has a rotation of the vibration plane, which electric field vector of the electromagnetic wave lies, on the transmission properties of the binary superlattice. In the literature, the most common transmission structure are given for the P or S wave polarization. This article aims to verify the nature of the transmission when the polarization is not strictly defined. Design/methodology/approach: In the paper the transmission of quasi one-dimensional binary structures is analized depending on the angle of incidence and wavelength of electromagnetic wave and on torsion angle of the plane of the electric field, using the matrix method. Findings: Changing the angle of rotation of the incident electromagnetic wave electric field vibration plane affects the size of the interband transmission and causes separation of fixed transmission bands locations for specific wavelength and angle of incidence. Research limitations/implications: Quasi one-dimensional binary superlattices composed of lossless, non dispersive isotropic materials were analyzed. It would be important to investigate influence of loss factor and the two- and three-dimensional periodic and aperiodic structures on the electromagnetic wave transmission. Also important would be to compare results with those obtained from the use of finite increments algorithm in the time domain (FDTD) and the correlation with experimental data. Practical implications: The test structures may be used as filters of electromagnetic wave propagation. The structure and thickness of the layers has a significant influence on the characteristics of the transmission, which will allow to design the structure in order to met the conditions of specific applications. Originality/value: In this paper, a method for the analysis of the electromagnetic waves transmission characteristics in the case where the electric field is not polarized in the S, or P directions only.
6
Content available remote Infrared transmission in aperiodic structures
EN
Purpose: The analysis of the electromagnetic wave transmission having a wave length near infrared propagating in multilayer structures made of materials GaP and CaF2. Analyzed was the influence of periodicity distribution of layers in the material properties and the presence of photonic forbidden gap for selected wavelengths of the electromagnetic wave. Design/methodology/approach: Maps transmission, which was performed by the analysis were obtained using a matrix method. Was investigated wave propagation wavelength range of infrared radiation in periodic binary multilayers and aperiodic Severin and Thue-Morse superlattices. Findings: It has been shown the structure of the transmission band depending on the type of polarization of the multilayer system. Properties of Thue-Morse superlattices were similar to binary superlattices but differed from the behavior of electromagnetic waves in aperiodic Severin superlattices. Research limitations/implications: The simulation was not considered the impact of losses in the material for propagating electromagnetic wave. Practical implications: Multilayer materials, which have photonic band gap, can be used as filters for electromagnetic radiation can improve the performance of night vision or electromagnetic waves multiplexers. Originality/value: Transmission properties of multilayers were examined in visible light but not for infrared light.
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