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1.
The origin of frequency gaps in the dispersion relation of periodic, quasi-periodic, and random photonic structures consisting of different arrangements of dielectric cylinders has been investigated. For TM polarization it was found that the formation and properties of gaps are strongly affected by Mie resonances of a single cylinder. Both the spectral position and size depend on the properties of this single scatterer. In contrast, for TE polarization no correlation between the scattering properties and bandgap formation was found, as Mie resonances are spectrally not well separated. For the inverted structure consisting of air cylinders in a dielectric material, the frequency gaps depend on the spatial arrangement of the cylinders because no pronounced Mie resonances exist in this case. 相似文献
2.
The transmission spectra of two-dimensional resonant photonic crystals of two types have been investigated. Crystals of one
type consist of dielectric cylinders forming a square lattice filled by a resonant gas with mercury atoms, and crystals of
the other type consist of cylindrical holes filled with a gas and forming a square lattice in a dielectric matrix. It has
been established that characteristics of the spectrum of additional transmission arising in the band gap of the photonic crystal
can be changed significantly by varying the gas pressure and the angle of incidence. It has been demonstrated that the calculated
features in the transmission spectrum of the photonic crystal are stable with respect to a significant increase in the width
of the atomic resonance. 相似文献
3.
M.V. Rybin A.B. Khanikaev M. Inoue A.K. Samusev M.J. Steel G. Yushin M.F. Limonov 《Photonics and Nanostructures》2010,8(2):86-93
We present a study of a Fano resonance between a narrow Bragg band and disorder-induced continuum in photonic crystals where the continuum is either of the broad band Fabry-Pérot scattering in an imperfect one-dimensional photonic crystal or Mie scattering in an imperfect three-dimensional photonic crystal. Our experimental studies of synthetic opals have demonstrated how the Fano resonance may lead to a transmission spectrum exhibiting a Bragg dip with an asymmetric profile or a Bragg rise. 相似文献
4.
《Physics letters. A》2006,359(6):723-727
Optical limitation in a 2D nonlinear photonic crystal (NPC) has been studied in this Letter. Since the optical limitation is due to Bragg scattering induced by the variation of nonlinear refractive index, it is sure that the optical limitation can be realized in nonlinear photonic crystal. The light propagation characteristics in a two-dimensional nonlinear photonic crystal with triangular lattice has been calculated by using the finite-difference time-domain algorithm, which is constructed by placing certain number of nonlinear dielectric rods in a linear photonic crystal. The optical limiting effects at 1.300 and 0.504 μm have been obviously obtained for TE polarization and TM polarization, respectively. 相似文献
5.
The mechanisms of formation of Bragg reflectance and transmittance spectra have been investigated for films of three-dimensional
opal-like photonic crystals. Attention has been drawn to the fact that the spectra exhibit an additional short-period interference
structure of the novel type due to the multiple Bragg diffraction of light. The spectra have been calculated in the framework
of the dynamical three-wave diffraction model taking into account strong spatial modulation of the dielectric function. It
has been found that short-period oscillations appear in the spectra due to the spatial quantization of additional modes with
a low group velocity. 相似文献
6.
This paper reports on a comprehensive study of optical transmissivity spectra of synthetic opals as a function of the four major parameters of the observed photonic stop bands, namely, light beam orientation relative to the opal fcc lattice, light polarization, opal-filler dielectric permittivity contrast, and sample thickness. The measurements were performed under low opal-filler dielectric contrast conditions for the principal high-symmetry directions of the twinned fcc lattice of the opals. The experimentally determined dependence of the energy positions of photonic stop bands on the direction of the light wave vector is fitted well by the calculated dispersion relation of Bragg wavelengths in diffraction of light from the (hkl) fcc plane system. 相似文献
7.
S. Bayan U. Das D. Mohanta 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2011,61(2):463-468
Barbules of the peacock feather have been used as the
natural template for developing assemblies of zinc oxide (ZnO) nanospheres.
The different colored barbules consisting of various photonic crystals
(extracted from eye-pattern) were characterized in terms of the stop-bands
identified in the respective Reflectance spectra. The stop-bands of the
photonic crystals are found to get red-shifted after the loading of ZnO
nanospheres and was reasoned to the modification of photonic band gap. The
ZnO nanosphere decorated barbules show well defined photoluminescence
response with dominant defect related emission of ZnO. The artificially
grown inorganic structures on natural templates form a basis of new hybrid
system that can help in exploiting photonic band gap engineering and light
wave modulation with high selectivity. 相似文献
8.
9.
The specific features of the transmission and reflection spectra of a one-dimensional photonic crystal structure with a magnetically active layer placed between dielectric Bragg mirrors have been investigated. If the magnetic resonance frequency coincides with the frequency of the defect mode in one of the photonic bands, the defect mode in the photonic crystal can be completely suppressed, which makes it possible to effectively control the spectrum of such a structure by an external magnetic field. 相似文献
10.
S. Ya. Vetrov N. V. Rudakova I. V. Timofeev V. P. Timofeev 《Optics and Spectroscopy》2012,112(4):585-593
We have studied the transmission spectra of resonant two-dimensional photonic crystals of two types, one of which consists
of nanocomposite cylinders that form a square lattice in vacuum and the other of which consists of cylindrical holes that
form a square lattice in nanocomposite matrix. The nanocomposite consists of metallic nanospheres that are dispersed in a
transparent matrix and is characterized by an effective resonant dielectric permittivity. We show that, depending on the position
of the resonant frequency of the nanocomposite with respect to the boundaries of the band gap, there arises either an additional
transmission band in the transmission spectrum in the band gap or an additional band gap in the continuous spectrum of the
photonic crystal. As the structural and geometric parameters of the system change, both the additional transmission band and
the additional band gap are considerably modified. We analyze particular features of the spatial distribution of the electromagnetic
field intensity in crystals. The considered effects can be used to extend the possibilities of creating new photonic crystals
with specified properties. 相似文献
11.
The transmission spectra of thin-film colloidal photonic crystals with three-dimensional and one-dimensional-two-dimensional
photonic energy band structures, i.e., opals and Langmuir-Blodgett crystals with a refractive index contrast of ∼1.5: 1.0,
have been measured in linearly polarized light. It has been demonstrated that the polarization anisotropy in the light transmitted
through the crystal is uniquely related to the diffraction resonance and that the degree of polarization can exceed 90%. A
higher degree of polarization is provided by lattices that are characterized by a smaller attenuation of light polarized in
the plane of incidence. It has been revealed that the diffraction resonances from the crystal planes for which the dispersions
are in anticrossing with the dispersion of the growth planes acquire the same anisotropy. The general character of the results
obtained has been confirmed by the fact that the polarization anisotropy identically manifests itself in colloidal crystals
that have different symmetries and lattice orderings. 相似文献
12.
A. V. Baryshev M. E. Dokukin A. M. Merzlikin M. Inoue 《Journal of Experimental and Theoretical Physics》2011,112(3):361-369
The interaction of linearly polarized light with photonic crystals based on bulk and thin-film synthetic opals is studied.
Experimental transmission spectra and spectra showing the polarization state of light transmitted through opals are discussed.
A change in polarization is found for waves experiencing Bragg diffraction from systems of crystallographic planes of the
opal lattice. It is shown that the polarization plane of the incident linearly polarized wave at the exit from photonic crystals
can be considerably rotated. In addition, incident linearly polarized light can be transformed to elliptically polarized light
with the turned major axis of the polarization ellipse. Analysis of polarization states of transmitted light by using the
transfer-matrix theory and homogenization theory revealed good agreement between calculated and experimental spectra. 相似文献
13.
14.
The band structure of two-dimensional resonant photonic crystals of two types has been calculated using the expansion of eigenfunctions
in plane waves. Crystals of one type consist of infinite dielectric cylinders forming a square lattice filled with a resonant
gas, and crystals of the other type consist of infinite cylindrical holes filled with a resonant gas and forming a square
lattice in a dielectric matrix. It has been shown that, in both cases, the dispersion of a resonant gas in combination with
the dispersion of a two-dimensional structure with a photonic band gap leads to the appearance of an additional narrow transmission
band near the edge of the band gap or an additional band gap in the continuous spectrum of the photonic crystal. The calculations
performed have demonstrated that new dispersion properties substantially depend on the density of the resonant gas, the position
of the resonant frequency with respect to the edge of the band gap, and the direction of propagation of electromagnetic waves. 相似文献
15.
A. G. Bazhenova A. V. Sel’kin A. Yu. Men’shikova N. N. Shevchenko 《Physics of the Solid State》2007,49(11):2109-2120
This paper reports on an experimental and theoretical study of the spectra of Bragg reflection of light from opal-like photonic crystals near the critical angle of incidence ? c , at which the Bragg reflection in the p polarization of reflected light disappears The objects studied were polymer photonic-crystal structures made up of polystyrene particles. It is shown that Bragg reflection for the electromagnetic TM mode becomes totally suppressed at an angle of incidence ? c , which depends on the geometric parameters and dielectric constants of the spatially periodic structure. 相似文献
16.
17.
In this paper, we have studied two-dimensional function photonic crystals, in which the dielectric constants of medium columns are the functions of space coordinates , that can become true easily by electro-optical effect and optical kerr effect. We calculated the band gap structures of TE and TM waves, and found the TE (TM) wave band gaps of function photonic crystals are wider (narrower) than the conventional photonic crystals. For the two-dimensional function photonic crystals, when the dielectric constant functions change, the band gaps numbers, width and position should be changed, and the band gap structures of two-dimensional function photonic crystals can be adjusted flexibly, the needed band gap structures can be designed by the two-dimensional function photonic crystals, and it can be of help to design optical devices. 相似文献
18.
Jing Li Hongfei Wang Shiyin Jia Peng Zhan Minghui Lu Zhenlin Wang Yanfeng Chen Biye Xie 《Laser \u0026amp; Photonics Reviews》2024,18(2):2300543
Topological phases based on tight-binding models have been extensively studied in recent decades. By mimicking the linear combination of atomic orbitals in tight-binding models based on the evanescent couplings between resonators in classical waves, numerous experimental demonstrations of topological phases have been successfully conducted. However, in dielectric photonic crystals, the Mie resonances' states decay too slowly as , leading to intrinsically different physics between tight-binding models and dielectric photonic crystals. Here, a confined Mie resonance photonic crystal is proposed by embedding perfect electric conductors between dielectric rods, creating the chiral symmetric band structure which ideally matches tight-binding models with nearest-neighbour couplings. As a consequence, disentangled band structure spanned by higher atomic orbitals is observed. Moreover, the result provides an effective route to achieve a 3D photonic crystal with a complete photonic bandgap and third-order topology. The implementation offers a versatile platform for studying exotic higher-orbital bands and achieving tight-binding-like 3D topological photonic crystals. 相似文献
19.
二维介质型光子晶体的直线法分析 总被引:1,自引:0,他引:1
运用直线法对二维介质型光子晶体的能带结构进行分析,给出直线法中关于二维介质型光子晶体的本征方程的建立过程.同时,对不同参数的光子晶体进行计算,计算结果通过时域有限差分算法(FDTD)及已发表的数据得到了验证,并考虑不同结构的光子晶体的TE波与TM波的带隙形成情况,可为二维介质型光子晶体的设计提供参考. 相似文献
20.
T. A. Ukleev N. N. Shevchenko D. I. Iurasova A. V. Sel’kin 《Physics of the Solid State》2018,60(5):916-920
The optical spectra of Bragg reflection from opal-like photonic crystals under conditions of the resonant enhancement of the multiple diffraction of light have been studied experimentally and theoretically using the photonic crystal structures prepared of monodisperse polystyrene globules. It is shown that the reflection signal registered in mutually orthogonal configurations of the polarizer and analyzer is related to the intrinsic optical anisotropy of the crystals and is a specific manifestation of the multiple Bragg diffraction in three-dimensional photonic crystals. 相似文献