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1.
The coexistence of TE-TM surface waves in uniaxially anisotropic left-handed materials 总被引:1,自引:0,他引:1
We investigate theoretically the characteristics of surface waves in uniaxially anisotropic left-handed materials. The constraints for the existence of TE and TM polarized surface waves in uniaxially anisotropic left-handed materials are identified. We discuss mainly whether TE and TM polarized surface modes may coexist in the same frequency domain at the interface between one isotropic regular medium and another uniaxially anisotropic left-handed medium. It is shown that the answer to the coexistence of TE and TM surface modes is really positive. The Poynting vector and the density of energy associated with surface modes are calculated. Depending on the system parameters either TE or TM surface modes has the time averaged Poynting vector directed opposite or same to the mode phase velocity. In the presence of anisotropy, negative refraction does not need to be left-handed. We show that the characteristics of surface waves in uniaxially anisotropic left-handed media are significantly different from that in isotropic left-handed media. 相似文献
2.
We investigate theoretically the creation conditions of TE and TM polarized surface waves created at the interface between a homogeneous medium and one dimensional photonic crystal (1D PC). The 1D PC is composed of uniaxially anisotropic left-handed (LH) and isotropic right-handed (RH) layers. We show that the characteristics of surface waves created in the 1D PC are significantly different from those created in the structure composed of isotropic LH and RH layers. We also prove that the coexistence of TE and TM surface waves at the interface is possible in the same frequency domain. Moreover, it is shown that in this structure backward and forward surface waves are created in wider ranges of frequency and angle of incident light, in comparison with the structure in which the left-handed layers are isotropic. 相似文献
3.
Beam-interface interactions under incidence of a TE polarized elegant Hermite–Gaussian beam are considered in order to obtain
efficient excitation of higher-order beam modes at a homogeneous, isotropic metamaterial surface. It is shown by numerical
simulations that two transmitted TE and TM polarization beam components are enhanced more efficiently at a metamaterial surface
than in the case of a dielectric interface. The mixed Poynting vector contribution to the incident energy flux is evaluated
to explain this enhancement. The numerical results obtained are verified against energy balance at the interface. 相似文献
4.
R. J. King 《Applied Physics A: Materials Science & Processing》1974,5(3):187-196
Expressions for the surface impedance and admittance, and the corresponding Fresnel reflection coefficients are derived for uniform plane TM and TE waves which are obliquely incident upon plane layered anisotropic media. The permittivity and permabi-lity tensors of each layer are assumed to be symmetric, and the propagation vector of the incident wave lies in one of the planes of anisotropy. The results can be used directly in well known formulas for groundwave propagation over isotropic media, and so there is no need to rederive these formulas for the various horizontal or vertical, electrical or magnetic dipole sources. The effect of the anisotropy upon the wave tilt is also discussed. 相似文献
5.
We study the transmission properties in the one-dimensional
photonic crystal containing alternate anisotropic left-handed
material (LHM) layers and regular isotropic right-handed material
(RHM) layers. For such an anisotropic case, the dispersion
relation from the Bloch theorem is derived and the Bragg gaps of
the periodic structure are observed. It is found that in the m=0
Bragg gap, there is an omnidirectionally reflectional (ODR)
region, which is also invariant with a change of scale length,
similar with the
[`(n)]=0\bar{n}=0
gap in isotropic one-dimensional
photonic crystal. With the aid of effective medium theory (EMT),
the analytic expressions of all six elements of the effective
electric permittivity tensor and magnetic permeability tensor are
obtained. By using these results, we investigate the ODR region in
the m=0 Bragg gap in all the possible cases of both TE and TM
modes. We find that with different choices of parameters, the
m=0 Bragg gap has different transmission properties, and the ODR
region in it changes, consequently. The edges of the ODR region
are given out in these cases. To one's interest, these results
predict a complete reflection region in the m=0 Bragg gap, which
is able to omnidirectionally reflect waves in both TE and TM modes. 相似文献
6.
Mengxia Yu Yonggang Wang Wu Zhong Ru Guo Xiuli Zhou 《Applied Physics A: Materials Science & Processing》2012,108(1):65-73
We study the behavior of wave propagation in strongly anisotropic metamaterials with different principal dielectric constants. Analytical expressions of the dispersion relation, Poynting vector, and group velocity are derived theoretically. The light propagation properties for TM and TE waves in these metamaterials are explored, in which the backward wave, negative refraction, phase-compensation effects, and far-field propagation wave carrying subwavelength information are discussed. These theoretical results are supported by numerical simulation. 相似文献
7.
8.
The possibility of the existence of a special class of surface electromagnetic waves with amplitude decreasing nonexponentially as they pass into an anisotropic metal–dielectric structure that borders the isotropic dielectric has been shown. The dispersion equation describing the propagation of such special surface waves has been obtained, and their attenuation coefficients and formula for electric and magnetic fields in contacting media have also been found. The expressions for the longitudinal and transverse components of the Poynting vector and volume density of electric and magnetic energy of special surface waves have been obtained. Numerical calculations for the layered metal–dielectric nanostructure that is described by a uniaxial tensor of effective dielectric permeability have been carried out Decaying. 相似文献
9.
We have investigated the nature of polaritons which propagate on the surface of semi-infinite anisotropic dielectric and magnetic media and find that the surface polaritons are regular surface waves [i.e., the penetration constant α (ω) is real] only for special orientations of the wave vector k and of the normal to the surface n relative to the principal axes. In the case of biaxial crystals, regular surface polaritons occur when k and/or n is along a principal axis of the dielectric tensor ε(ω) for dielectric media [or the magnetic permeability tensor μ(ω) for magnetic media]. When k and n are both directed along principal axes, the surface polaritons are TM with E in the saggital plane for dielectric media. One finds that surface polaritons which are coupled photon-virtual surface dipole excitation modes can exist on “surface active” anisotropic media in addition to the familiar coupled photon-real surface dipole excitation modes. When neither k nor n are along principal axes, the surface polaritons that occur are, with the exception of special orientations, “generalized” surface waves [i.e., α(ω) is complex]. The Poynting vectors of the propagating surface polaritons are always in the plane of the surface but not, in general, along k. These results, which hold for uniaxial crystals, are also applicable to gyromagnetic media and to gyrodielectric media. This theory is also applicable to surface polaritons which propagate along the interface between two media, one or both of which is anisotropic, and with one or the other serving as the “surface active” medium. 相似文献
10.
11.
G. T. Adamashvili 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2012,66(4):101
A theory of an optical vector breather of self-induced transparency of surface plasmon polaritons is constructed. The nonlinear
surface TM-modes propagating along the interface separating an isotropic medium and anisotropic left-handed material are investigated.
A transition layer sandwiched between the connected media is described using a model of a two-dimensional gas of semiconductor
quantum dots. Explicit analytical expressions for the shape and parameters of the surface vector breathers are obtained as
well as simulations of the space-time dynamics of two-dimensional vector breathers presented with realistic parameters which
can be reached in current experiments. It is shown that properties of a surface vector breather with phase modulation depends
on the parameters of the quantum dots, the connected media and the transverse structure of the surface wave. 相似文献
12.
Yenny Pinto Julien Sarrazin Anne-Claire Lepage Xavier Begaud Nicolas Capet 《Applied Physics A: Materials Science & Processing》2014,117(2):693-697
This paper presents a lightweight microwave absorber suitable for space applications. The absorber is based on a resistive high-impedance surface (RHIS) optimized to achieve reflection under ?15 dB in the band (2–2.3 GHz) at oblique incidence for transverse electric (TE) and transverse magnetic (TM) polarizations. A first classical isotropic RHIS structure is shown to be limited to angles of incidence up to 40° for TE polarized waves and up to 35° for TM polarized waves. So the objective of this contribution is to present a second solution based on an anisotropic RHIS structure which presents good absorption of incident waves in TE and TM polarizations for larger angles of incidence. An example is presented for an incidence angle of 65°. 相似文献
13.
14.
Abstract The optical characteristics of the TE and TM guided modes of a multilayer anisotropic two-dimensional waveguide are investigated by using the field component transformation matrix, and also taking into account the substrate intrinsic dispersion. The embedded thin metal layer effects on the propagation constant for both lossless approximated and exact solutions are presented. The lossless approach is accurate enough for the TE waves, but it is not for the TM ones, which exhibit changes of about 10?6 for the equivalent index. The TM modes also present attenuation constant changes between the lossy and weakly-lossy solutions of the order of 9 dB/cm. Several complex field component mappings are drawn, and the surface plasma waves are also examined. 相似文献
15.
An Ping Zhao 《Optical and Quantum Electronics》1995,27(8):735-740
The intensity-dependent characteristics of nonlinear TE and TM waves in a thin film bounded by lossy nonlinear media are analysed by the finite-element method. In this approach, the power-dependent complex propagation constants and local complex electromagnetic field distributions of lossy nonlinear TE and TM waves are obtained directly from the given lossy nonlinear waveguides, without any approximations. Numerical results for these modes in a lossy nonlinear waveguiding system with different absorption coefficients are given. It is shown that the complex dispersion relations, for both TE and TM modes, are strongly power dependent. 相似文献
16.
Surface waves that propagate along the interface between an isotropic linear or nonlinear (of the Kerr type) dielectric and a topological insulator have been studied theoretically. A dispersion relation for surface waves, which are represented by superpositions of TE and TM waves, has been obtained. This hybridization occurs because, upon passage through the interface, the polarization of a surface wave changes, which is caused by an induced surface current (which is transverse to the electric field vector of the wave). The surface current of this kind is characteristic of topological insulators. Expressions for the energy flux transferred by a surface wave have been given. 相似文献
17.
The refraction of a plane wave into a uniaxial crystal with possible absorption is analysed. The Poynting vector of the transmitted wave is formulated and succinct conditions for the decomposability of its normal component into the normal components of the Poynting vectors of the ordinary and extraordinary refracted waves are derived. The implications for raytracing in anisotropic media with absorption are discussed. 相似文献
18.
The TE/TM polarization conversion characteristics of dielectric grating composed of left-handed materials for the case of
plane wave oblique incidence are carefully investigated by a method which combines the multimode network theory with the rigorous
mode matching method. It is indicated that complete polarization conversion between TE and TM modes can be realized using
left-handed gratings. This can hardly achieve in the conventional right-handed gratings. Comparisons of polarization conversion
properties between right-handed gratings and left-handed gratings are given with physical explanations. This unique merit
of left-handed periodic structure is of important significance for accurate design of new millimeter wave TE/TM polarization
converters. 相似文献
19.
从Maxwell方程组出发,讨论纤芯为左手材料,包层为右手材料阶跃型光纤,推导了矢量解的场方程.经过数学计算,求得了左手材料阶跃型光纤矢量解的特征方程.根据矢量模的分类,找到了TE模、TM模、HE模和EH模的特征方程.根据各模的特征方程,并且与右手材料光纤相关的特征方程,在靠近截止和远离截止两种情况下进行了比较,得到了左手材料光纤的某些奇异特性. 相似文献
20.
Nicolas L. Dmitruk 《Optics Communications》2011,284(19):4254-4258
New formulae for the angles of refraction at the interface of the absorbing/transparent isotropic media are derived from Maxwell's equations. Using the time-averaged Poynting vector for the direction of the beam of light, the noncoincidence of incidence and refraction planes is predicted for the mixed polarization of incident wave. The angle between the refracted beam and incidence plane is especially large for the condition of non-resonant excitation of surface electromagnetic waves at a flat interface of absorptive-transparent media. 相似文献