共查询到20条相似文献,搜索用时 15 毫秒
1.
We demonstrate the possibility of a unique reconstruction of the coordinate dependence of all dielectric permittivity tensor
components of an absorbing one-dimensionally inhomogeneous plate with any symmetry (except for 1, 2, and m classes) and a negligibly small spatial dispersion. This reconstruction can be performed, the zone of the strong frequency
dispersion of the medium inclusive, provided that the reflection and transmission coefficients for the p- and s-polarized plane monochromatic waves are known in a certain range of incidence angles. 相似文献
2.
A method for modeling the radial distribution function for particles of a two-dimensional planar photonic crystal in the form
of a monolayer of spatially ordered monodisperse spherical particles is proposed. The coherent transmission and reflection
coefficients for layers under normal illumination are calculated in the quasi-crystalline approximation of the multiple wave
scattering theory. The dependence of the coherent transmission and reflection of the layer on the degree of ordering of the
spherical particles is investigated. The influence of the long-range order on the coherent transmission and reflection coefficients
for layers with triangular, square, and hexagonal lattices is estimated. Monolayers of weakly absorbing dielectric and strongly
absorbing metallic particles are considered. 相似文献
3.
An approximate method is developed for investigating the nature of interface exciton modes in a composite spatially dispersive
medium. The method is general enough to be applicable to any composite system, in which each component is described by an
arbitrary bulk dielectric functionε(q, ω). It is based on the extension of the usual electrostatic-image method of solving the Poisson’s equation, in the presence
of an external point charge in the system. We have applied our general method to a composite system of a finite metal slab
surrounded by a semiconductor on one side and the vacuum on the other side. Similarly, we have also considered the case of
a metallic sphere of radiusR, surrounded by a semiconductor, with a spherical interface between them. With assumed spatially dispersive model dielectric
functions for the bulk metal and the bulk semiconductor, the nature of the electron-electron interaction and the interface
exciton modes in the metallic region are obtained in both the cases. For the relevant size of the metal large compared to
the atomic dimensions over which the bulk dielectric functions are non-local due to the spatial dispersion, it is shown that
one can obtain the interface exciton modes by first defining new effective dielectric functions for each of the media making
the particular interface, and then using the usual expression which determines the modes in the non-dispersive case. 相似文献
4.
We present a new scheme to report on Goos–Hänchen (GH) shift experienced by the Gaussian light beam interacting with an optical cavity filled with four-level sodium atomic medium in the spectral hole burning region with and without Doppler broadening effect. Theoretical atomic density-matrix formalism is employed to obtain the susceptibility of atomic medium while the stationary-phase-theory is used to compute the GH shift in the reflected and transmitted probe beams subjected to control fields. A steep normal slope of dispersion is observed with a maximum and zero probability of transmission and reflection coefficients, respectively, at the regions of the spectral holes burning. In the normal dispersion spectrum at the region of spectral hole burning, positive and negative GH shift is observed, respectively, in the transmitted and reflected light beams. However, at anomalous dispersive regions negative GH shift in the transmission beam and positive GH shift in the reflection beam is observed. The reflection and transmission coefficients as well as the spatial GH shift are the functions of probe detuning, collective phase of control fields, beam incident angle and inverse Doppler broadening effect in the spectral hole burning region. The position and number of spectral holes also depend on the same spectral parametrs as stated above. The study is expected to be useful for optoelectronic devices and optical-clocking applications. 相似文献
5.
Hongwei Yang R. S. Chen Yongchun Zhou 《International Journal of Infrared and Millimeter Waves》2007,28(9):751-758
In this paper, a novel finite-difference time-domain (FDTD) method with recursive relationships among operators is developed
for magnetized dispersive medium, named as the shift operator FDTD(SO-FDTD). The dielectric property of magnetized dispersive
medium is written as rational polynomial function, the relationship between D and E is deduced in time-domain. And its high accuracy and efficiency are verified by calculating the reflection and transmission
coefficients of electromagnetic waves through a collision plasma slab. 相似文献
6.
7.
We present a theory of the photonic band structure of three-dimensional arrays of quantum dots (QDs). A system of Maxwell’s and material equations is solved and the dispersion equation for exciton-polaritons is derived making allowance for a nonlocal dielectric response of quasi-zero-dimensional excitons confined in QDs. The reflection and transmission coefficients are calculated for a single plane, a pair of planes and a stack of equidistant planes of QDs. Two different approaches are proposed to perform a calculation. One of them is based on recurrent equations relating the reflection coefficients for N + 1 and N planes, while in the other approach the Bloch solutions for an infinite QD lattice are used. 相似文献
8.
M. M. Carroll 《Applied Physics A: Materials Science & Processing》1979,19(3):321-329
A time-sinusoidal circularly polarized plane standing wave solution is obtained for isotropic lossless dielectric media with
arbitrary nonlinearity. The spatial variation of the standing wave depends on the nonlinearity and is found by solving a problem
of centralforce motion in which the electric complementary energy density furnishes the potential and the spatial coordinate
has the role of time. Two special nonlinear dielectric response laws-cubic and quintic-are treated, and explicit solutions
for the spatial variation of the wave amplitude and phase are obtained in terms of elliptic functions and elliptic integrals,
respectively. The standing-wave solution is applied to give steady state solutions of two reflection/transmission problems
(a) reflection from, or resonance modes between, ideally conducting planes and (b) reflection and transmission at a plane
interface between two nonlinear dielectric media. 相似文献
9.
10.
Ferydon Babaei 《Optics Communications》2008,281(11):3120-3130
The transmission and reflection spectra from a right-handed chiral sculptured zirconia thin film are calculated using the piecewise homogeneity approximation method and the Bruggeman homogenization formalism using both dispersive and non-dispersive functions for axial and non-axial states. The comparison of spectral results shows that the dispersion of the dielectric function has a considerable effect on the results. In axial excitation of cross-polarized reflectances and co-polarized transmittances the dispersion effect becomes more pronounced at wavelengths further away from the homogenization wavelength. This is also true in the case of non-axial excitation of circular transmittances, while there are considerable differences for cross-polarized reflectances where (wavelength) the first Bragg peak occurs. At wavelengths in the vicinity of the homogenization wavelength the dispersion effect of the dielectric function in RRR becomes more significant. 相似文献
11.
We have calculated the transmission and reflection coefficients for a surface polariton that is incident normally on the interface between two different surface active dielectric media characterized by real, scalar, frequency dependent dielectric functions. Numerical solutions are obtained by matching the boundary conditions for the electromagnetic fields at the interface between the media and between each medium and the vacuum above it. The energy carried away by the vacuum modes is also calculated. 相似文献
12.
V. Kalesinskas A. Konstantinov V. Shugurov 《International Journal of Infrared and Millimeter Waves》1998,19(12):1773-1781
The paper presents a rigorous solution of the scattering problem by a circular dielectric and perfectly conducting cylinders of any radius and any height in the rectangular waveguide oriented perpendicularly to a wall. The method is based on the representation of fields in waveguide and dielectric medium by cylindrical eigenfunctions and application of boundary conditions on surfaces of the cylinder to evaluate the fields inside and outside the cylinder. The reflection and transmission coefficients are expressed through the fields. As an example the reflection and transmission coefficients versus frequency for various dielectric and metallic cylinders are computed. The comparison of numerical with experimental data is presented. 相似文献
13.
将一类色散介质的介电常数写成有理分式函数形式,进而导出FDTD中电位移矢量D和电场强度E之间的关系,形成SO-FDTD方法. 应用该方法计算了冷等离子体平板对电磁波的反射系数,通过与解析结果的比较,验证了该算法的高效性和高精度,同时,应用SO-FDTD方法,计算了等离子体层对垂直入射电磁波的反射系数,结果表明:等离子体厚度、电子密度、电子密度的分布形式和入射波频率是影响反射系数的重要因素.
关键词:
等离子体
电磁波
FDTD方法 相似文献
14.
The dispersion relations of the surface polariton in a semi-infinite wire medium with spatial dispersion are analysed. In comparison with the traditional spatial dispersive medium there only exists one branch instead of multibranch for the dispersion curve. The possibility of the experimentally observing the surface polaritons by attenuated total reflection is simulated numerically. 相似文献
15.
M. K. Balyan 《Journal of Contemporary Physics (Armenian Academy of Sciences)》2016,51(4):391-397
Diffraction of a spatially inhomogeneous X-ray wave was theoretically studied in a crystal with cubic nonlinear response to the strength of an external electric field. Using numerical calculations in case of two-beam diffraction of a narrow incident beam, the intensity distributions on the output surface of the crystal was investigated depending on the thickness and intensity of the incident beam. The results of numerical calculations of integral (spatial) coefficients of transmission and reflection are given as functions of incident wave intensity for fixed thickness of the crystal. 相似文献
16.
The surface impedance for non-normal specular reflection from a spatially dispersive medium is calculated using the additional boundary condition of vanishing polarization at the surface. There is no dependence on the longitudinal dielectric constant for either polarization directions of the electric field in contrast to the formula derived by Kliewer and Fuchs. 相似文献
17.
The results of analytical modeling of the resonant excitation of evanescent harmonics in a medium formed by parallel metallic
nanorods taking into account the spatial dispersion are presented. Analytical expressions are derived for the reflection and
transmission coefficients, as well as for the amplitudes of electromagnetic waves inside the medium. These expressions are
compared to similar expressions that were previously obtained using a local model of an ultimately anisotropic material without
taking into account the spatial dispersion. The obtained expressions are simplified for various partial cases, including the
superresolution imaging of a source that is located at a considerable distance from the metamaterial layer. A layer of a medium
composed from finitesized wires is numerically simulated and it is demonstrated that, due to the effect of resonant excitation
of evanescent spatial harmonics in the layer, subwavelength details of an object that is considerably distant from the layer
can be distinguished inside of the layer. 相似文献
18.
We show that absorbed and stored electromagnetic energy are proportional to the reflection group delay in highly reflective dispersive dielectric mirrors over the high-reflectivity band.Our theoretical considerations are verified by numerical simulations performed on different dielectric mirror structures.The revealed proportionality between group delay and absorbed energy sets constraint on the application of ultrabroadband and/or dispersive dielectric mirrors in broadband or widely tunable,high-power laser systems. 相似文献
19.
Clausnitzer T Kämpfe T Brückner F Heinze R Kley EB Tünnermann A 《Optics letters》2008,33(17):1972-1974
We present the design and realization of a highly dispersive dielectric transmission grating with 97.0% diffraction efficiency. This grating is embedded in fused silica, which allows for an efficient suppression of any reflection losses. It is very easy to handle and clean, and its monolithic layout gives rise to high resistance against laser-induced damage and long-term stability comparable to conventional fused silica components. 相似文献
20.
D. I. Sementsov 《Russian Physics Journal》1982,25(3):277-282
The distinctive features of the interaction of light with a banded domain structure produced by linear magnetooptical effects are discussed. A dispersion law for characteristic circular waves is found which contains regions of forbidden spatial frequencies in which the interaction of light with the structure is of a resonance nature. Dependences of the reflection and transmission coefficients and angle of rotation of the polarization plane on frequency and crystal size are obtained for these regions.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 3, pp. 84–88, March, 1982. 相似文献