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The boundary conditions of the moving layered medium are analyzed and the expressions of electromagnetic field are deduced. The reflection and transmission coefficients in fixed coordinates are obtained by using the covariance characteristic of Maxwell Equations. It is very complicated to apply boundary conditions many times in analyzing a multi-layer slab. In this paper, the results obtained from the boundary conditions of single-layer slab are analogous with those obtained by the transfer matrix method. Through improvement and generalization, the transfer matrix method can be used to calculate the moving multi-layer slabs. It can be applied to calculate the reflection and transmission coefficients of one-dimensional moving photonic crystal as well as deal with TM and TE polarization for the oblique incident. The zero reflection points of TM and TE polarization for layered slab are calculated. The results calculated in this study are matching well with the reference. It shows that the reflection oscillation enhances with the increase of β and layer number, while the changing rule of reflections about TM polarization is relatively complex. The reflections of both TE wave and TM wave are all related to the incidence angle. [ABSTRACT FROM AUTHOR]

Photonic crystal is a dielectric structure arranged according to certain rules, and its excellent electromagnetic wave characteristics can be used to manufacture a lot of kinds of photonic crystal devices. In this paper, a defect is introduced into the photonic crystal, and the transfer matrix method is used to study the relationship between the liquid concentration and the peak value of the liquid transmission at the electromagnetic wave length when the defect is a mixture of ethanol and glycol. The results show that by observing and measuring the position of the peak transmittance of the mixed liquid, the substance content of the liquid mixture, that is, the concentration, can be inferred. The accuracy of this method is compared with the experimental results, which shows that this method has high accuracy. This method is simple and easy to operate. This result opens up a new direction for the application of photonic crystals. [ABSTRACT FROM AUTHOR]

Boltzmann equation is carried out to study the micromechanism of interaction between electromagnetic wave and plasma. The Boltzmann-FDTD iteration formula that is about electromagnetic wave obliquely incident into plasma under one-dimensional case is deduced. The reflection coefficient and transmission coefficient of the plasma flat are calculated when the electromagnetic wave incidents into plasma medium at different incident angles. The correctness of the algorithm is proved through some examples in this paper. The change law and mechanism of the electromagnetic wave energy, the reflection coefficient, and incidence coefficient with the changing of the incident angle are analyzed. The evolution law when the distribution function of particles of plasma is acting with electromagnetic wave is study. This work will help us to study the macro and micro relationship about plasma matters in the future. [ABSTRACT FROM AUTHOR]

In this article, an anisotropic magnetized ferrite photonic crystal model is analyzed by using the finite-difference time-domain method. The electromagnetic wave propagates in anisotropic ferrite material and forms two kinds of Eigen propagation mode: left-hand circular polarization (LCP) mode and right-hand circular polarization (RCP) mode. Therefore, the ferrite material is used to produce photonic crystal and wave polarized by these two kinds of polarization modes can be obtained. Because the electromagnetic properties of the ferrite material are greatly influenced by the bias magnetic field, the ferrite photonic crystal band gap can be controlled by adjusting the intensity of the bias magnetic field, and then a magnetron photonic crystal filter is formed. The results show that the magnetic photonic crystal with the bias magnetic field to the LCP/RCP wave forms different pass band and band gap, which can obtain different forms of polarized wave. [ABSTRACT FROM AUTHOR]

Take Runge-Kutta exponential time differencing finite-difference time-domain (RKETD-FDTD) method, simulate numerically, analyze the transmission properties of terahertz (THz) wave in the non-magnetized plasma medium, and conclude the regulations of THz wave's frequency domain transmission characteristics vary with the parameters like plasma electron density and collision frequency. The results show that when the incident electromagnetic wave frequency is lower than 0.1 THz, the transmission coefficient of the plasma slab has close relationship with the electromagnetic wave's incident frequency, plasma electron density, and plasma collision frequency. The curve is of varied complex. When the incident electromagnetic wave frequency is between 0.1 and 10 THz band, the plasma slab has good transmission characteristics and its transmission coefficients are close to 0 dB. The transmission coefficient is almost not related to the electromagnetic wave incident frequency, the plasma electron density, and the plasma collision frequency. Analysis of these features will help further to apply THz in anti-plasma stealth, biological detection, transport safety checks, and other valuable areas. [ABSTRACT FROM AUTHOR]

The Symplectic Finite-Difference Time-Domain (SFDTD) method was applied to simulate the one-dimensional unmagnetized Plasma Photonic Crystal (PPC) with a sandwich structure. Compared with the traditional Finite-difference Time-Domain (FDTD) method, the results from the SFDTD method are reliable and accurate. Also the SFDTD method has better numerical dispersion characteristics than the traditional FDTD method and the Multi-Resolution Time-Domain (MRTD) method too. Electromagnetic propagation process by differential Gaussian pulse is given in the PPC band gap with the SFDTD method used. The influence of the plasma frequency and the thickness ratio of plasma and medium to PPC on the band gap structure is analyzed. The plasma frequency most affects the PPC in low-frequency range. Also the propagation of an electromagnetic wave can be controlled by the thickness ratio of plasma and medium. The results above prove that the SFDTD method can give the right and better results on the research of PPC. [ABSTRACT FROM AUTHOR]

For the first time, the current density convolution finite-difference time-domain (JEC-FDTD) method is extended to dispersive media using Crank–Nicolson difference scheme, and derive the one-dimensional JEC-CN-FDTD iterative equation of plasma. The incomplete Cholesky conjugate gradient (ICCG) is proposed to solve the large sparse matrix equation in the Crank–Nicolson finite-difference time-domain (CN-FDTD) method as the ICCG method improves speed of convergence, enhances stability and reduces memory consumption. The high accuracy and efficiency of the JEC-CN-FDTD method are confirmed by computing the characteristic parameters of electromagnetic wave through a collision plasma slab in one dimension, such as the reflection electric field, transmission electric field, magnitudes and phases of reflection coefficient and transmission coefficient. The results prove that the method performs stably, is of accuracy, and has certain advantages. [ABSTRACT FROM AUTHOR]

We extended the current density convolution finite-difference time-domain (JEC-FDTD) method to plasma photonic crystals using the Crank-Nicolson difference scheme and derived the one-dimensional JEC-Crank-Nicolson (CN)-FDTD iterative equation of plasma photonic crystals. The method eliminated the Courant-Friedrich-Levy (CFL) stability constraint and became completely unconditional stable form. The incomplete Cholesky conjugate gradient (ICCG) algorithm is proposed to solve the equation with a large sparse matrix in the CN-FDTD method as the ICCG method improves the speed of convergence, enhances stability, and reduces memory consumption. The JEC-CN-FDTD method is applied to study the characteristics of time domain and frequency domain in the plasma photonic crystal objects. The high accuracy and efficiency of the JEC-CN-FDTD method are confirmed by computing the characteristic parameters of plasma photonic crystals under different conditions such as the electric field distribution of electromagnetic wave, reflection coefficients, and transmission coefficients. Simulation study showed that the algorithm performed stably and could reduce memory consumption and facilitate computer programming. [ABSTRACT FROM AUTHOR]

The advantage of the ICCG method for solving large sparse matrix is taken in the CN–FDTD equation solving. The CN–ICCG–FDTD can accelerate iteration for numerical calculation, and reduce memory overhead. Maxwell's equation of the electromagnetic wave in dispersive medium plasma is deduced from the CN format after being differentiated in the time domain, the FDTD method become unconditionally stable. In this process, a large sparse matrix is generated. As for solving such matrix, ICCG method has sufficient advantages. In ICCG method, convergence is so fast and stable that it is quite easy for computer programming. In addition, data required by ICCG method are memorized in a computer in the format of the one-dimensional compression, which helps the computer memory save a large amount of capacity, especially when the issues are rather complex to cope with, this algorithm will display such strength. With these advantages, ICCG method is able to calculate the reflection coefficient and the transmission coefficient of electromagnetic waves in plasma as well as the phase angle of them. The calculation indicates that the time step required by CN–ICCG–FDTD method has eliminated the constraints of the CFL, thus shortening the required time, making the calculated result stable and accurate, and improving the efficiency of programming. [ABSTRACT FROM AUTHOR]

Abstract: Shift operator finite-difference time-domain (SO-FDTD) method is developed to study the stealth technology of inhomogeneous magnetized plasma in this paper. The high accuracy and efficiency of this method is verified by computing the reflection and transmission coefficients of electromagnetic wave through a collisional magnetized plasma slab in one dimension. The stealth effect of radar targets covered with Epstein distribution inhomogeneous magnetized plasma is studied. The results show that the stealth effect of radar targets covered with Epstein distribution inhomogeneous magnetized plasma is better than that of radar targets covered with homogeneous magnetized plasma. [Copyright &y& Elsevier]

Abstract: In this paper, a model for calculating the reflection and absorption powers of electromagnetic wave (EM wave) in nonuniform magnetized plasma slab is given out based on layer propagation theory. The effects of various plasma parameters and different values of magnetic field intensity on the reflected and absorbed powers are discussed. The results illustrate that the thickness of plasma seldom affects the reflection of radar wave, but it can broaden or reduce the absorption width. Meanwhile, the background magnetic field intensity has an influence upon the results, and it could change the resonance spectrum of magnetized plasma. We also find out that, with appropriate plasma density, collision frequency and magnetic field intensity, more than 90% of radar wave power can be absorbed and the resonant absorption band is about 2GHz. [Copyright &y& Elsevier]

Abstract: In this paper, the shift operator finite difference time domain (SO-FDTD) method and Runge-Kutta exponential time differencing (RKETD) method are introduced. The high accuracy and efficiency of the two methods are verified by calculating the reflection and transmission coefficients of electromagnetic waves through a collisional plasma slab. A comparison of computational efficiency of the two methods is presented by simulating the electromagnetic wave propagation in homogeneous non-magnetized plasma. The numerical results indicate that the calculation time using SO-FDTD method is less than that using RKETD method with almost the same accuracy. [Copyright &y& Elsevier]

Abstract: Numerical simulation of interaction between plasma slab and electromagnetic wave which has different incident frequency and incident angle is discussed in this paper. Some parameters contain reflection coefficient, transmission coefficient, reflectance, transmittance and phase are calculated by transfer matrix method. The relation of these parameters with incident frequency and incident angle is analyzed. The results show that the incident angle has low influence on the parameters when the angle varies from 0° to 30° and from 70° to 90°, but it has high influence on the parameters when it changes from 30° to 70°. These rules have certain directive significance to the research of interaction between oblique incidence electromagnetic wave and plasma slab and to the design of plasma layer. [Copyright &y& Elsevier]

Two new asymmetric slab optical waveguides with a left-handed media (LHM) cover or substrate are studied. The effective thickness is derived by using normalized waveguide parameters. An analytical method is then proposed to calculate the universal effective thickness. We show that negative effective thickness exists in the waveguide with a LHM substrate, unlike in conventional waveguide or other LHM waveguides studied previously. However, for the waveguide with a LHM substrate, the shape of high-order mode behaves like that of a traditional slab waveguide, and neither the fundamental mode nor the other higher order modes have the novel phenomena of negative effective thickness. Both TE and TM modes are discussed. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, the coefficient of reflection and transmission of electromagnetic wave on corn leaf are computed under room temperature. The relationship is given when the thicknesses of leaves are 0.5mm, 1.0mm and 1.5mm and the proportion of water in the weight are 0.25, 0.5 and 0.68. The rules are concluded that there would be longer period and easier expression of the two coefficients on the incident electromagnetic wave, when leaf is thicker or the proportion of water is heavier. On the contrary, opposite results are obtained. There are less affection that the changes of the leaves thickness on the maxima of the reflectance coefficient and the average of the transmission coefficient, but add the proportion of water can less increase maxima of reflect coefficient, at the same time, the average of the transmission coefficient will come down. [Copyright &y& Elsevier]

Abstract: In this paper, shift operator finite-difference time-domain (SO-FDTD) method is applied for the calculation of the dispersive medium. The high efficiency and accuracy of this method is verified by calculating the reflection of the plane electromagnetic wave impinging on a muscle slab. For human tissues where multiterm Debye relaxation equations must generally be used. We describe a new differential equation approach, which can be used for general dispersive media. In this method D(t) is expressed in terms of E(t) by means of a differential equation involving D, E, and their time derivatives. The method is illustrated by means of example of media for which relative permittivity is given by a multiterm Debye equation, and for an approximate two-thirds muscle-equivalent model of the human body. [Copyright &y& Elsevier]

Abstract: The precision and computational efficiency of the shift operator finite-difference time-domain (SO-FDTD) method are compared with those of the piecewise linear current density recursive convolution (PLCDRC) method by simulating the electromagnetic wave at different frequency propagation in homogeneous unmagnetized plasma in this paper. The results show that the two methods almost have the same precision, but the CPU time of the SO-FDTD method is less than that of the PLCDRC method, this is because the SO-FDTD method eliminates many convolution operations of the PLCDRC method. [Copyright &y& Elsevier]