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异质镜像光子晶体的光子带隙研究 总被引:1,自引:0,他引:1
对异质镜像结构光子晶体(ABCCBA)N进行了研究。首先,利用一维介电体系中处理光传播的方法--传输矩阵法,详细推导了异质镜像光子晶体透射率的计算公式;然后,采用Matlab软件编程仿真并分析了光子带隙形成与镜像周期数目、光子带隙数目与光子晶体薄层厚度、光子带隙位置与入射角大小等的关系。结果表明:光子带隙的形成及变化主要受光子晶体薄层厚度及入射角大小变化的影响。通过改变影响光子晶体光子带隙的参数,可得到不同频段的光子带隙,用来制作高质量反射镜、滤波器和发光二极管等。 相似文献
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Three-dimensional SiO2 photonic crystals (PhCs) are fabricated on quartz substrates by the vertical deposition method. Scanning electron microscopy measurement reveals that the samples exhibit an ordered close-packed arrangement of SiO2 spheres. It is found that the position of the [111] photonie band gap (PBG) shifts to a long wavelength (red shift) with increasing sphere size. Gap broadening effects are observed due to the presence of defects in the samples. Moreover, the optical properties of the PBG are very sensitive to the annealing temperature. Our results indicate that the optical properties of the PBG can be easily tuned in the visible region by appropriate experimental parameters, which will be useful for practical applications of PhC optical devices. 相似文献
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基于平面波展开法,设计缺陷态二维正方晶格光子晶体结构,改变构成缺陷态结构的材料、占空比,应用Matlab语言计算机仿真得到,高介电常数材料构成的缺陷态光子晶体形成较宽的横磁波光子带隙,占空比在30%时形成较宽的横磁波光子带隙.研究结论为缺陷态光子晶体滤波器件的制作提供理论依据. 相似文献
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We developed photochemically controlled photonic crystals which may be useful in novel recordable and erasable memories and/or
display devices. These materials can operate in the UV, visible or near IR spectral regions. Information is recorded and erased
by exciting the photonic crystal with ∼ 360 nm UV light or ∼ 480 nm visible light. The recorded information is read out by
measuring the photonic crystal diffraction wavelength. The active element of the device is an azobenzene functionalized hydrogel
which contains an embedded crystalline colloidal array. UV excitation forms cis-azobenzene while visible excitation forms
trans-azobenzene. Larger dipole moment of the cis-form results in decrease of the free energy of mixing which causes the hydrogel
to swell and to red-shift the photonic crystal diffraction with a 36 s time constant. We also observed fast ms and sub-ms
transient dynamics associated with convection due to heating of the medium by UV excitation. Convective motion of the medium
stretches the PCCA for about 6 μs within which the convection decays and the elastic restoring force of the PCCA brings back
the stretched PCCA to its equilibrium state with 33 μs time constant.
Paper presented at the 2nd International Conference on Ionic Devices, Anna University, Chennai, India, Nov. 28–30, 2003. 相似文献
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N. V. Tcherniega A. D. Kudryavtseva M. I. Samoylovich 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2008,2(4):624-630
The results of study of the photonic flame effect observed in photonic crystals and nanocomposites based on opal matrixes are presented. The effect has been discovered recently [1] and manifests itself as radiation with duration of a few seconds in the blue-green spectral region under excitation by pulsed laser light with a wavelength of 694.3 nm and a pulse duration of 20 ns. 相似文献
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By offering greatly enhanced control of light compared to conventional step-index structures, photonic crystal fibres are radically improving the performance of linear and nonlinear fibre devices, including gas-Raman cells, super-continuum generators, soliton systems and cladding-pumped lasers. 相似文献
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Lasing at resonantly coupled whispering-gallery mode frequencies is observed in photonic molecules consisting of bispheres of 4.2 and 5.1 microm in diameter placed in a silicon V-groove. We examine spatial profiles of photonic molecule modes by use of frequency-resolved imaging and reveal bonding and antibonding mode features. From the lasing threshold characteristics, we quantitatively measure the quality factor and the spontaneous-emission coupling ratio of the photonic molecule modes and confirm that strong coherent coupling leads to photonic molecule modes. 相似文献
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《中国科学:物理学 力学 天文学(英文版)》2010,(7)
Feshbach resonance is a resonance for two-atom scattering with two or more channels,in which a bound state is achieved in one channel.We show that this resonance phenomenon not only exists during the collisions of massive particles,but also emerges during the coherent transport of massless particles,that is,photons confined in the coupled resonator arrays linked by a separated cavity or a tunable two level system(TLS).When the TLS is coupled to one array to form a bound state in this setup,the vanishing transmission appears to display the photonic Feshbach resonance.This process can be realized through various experimentally feasible solid state systems,such as the couple defected cavities in photonic crystals and the superconducting qubit coupled to the transmission line.The numerical simulation based on the finite-different time-domain(FDTD) method confirms our assumption about the physical implementation. 相似文献
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M. V. Vasnetsov V. A. Pas’ko T. N. Orlova D. A. Plutenko A. D. Kudryavtseva N. V. Tcherniega 《Journal of Experimental and Theoretical Physics》2018,126(5):579-591
The Bragg diffraction in synthetic opal as a 3D photonic crystals has been analyzed using the weak disorder model in various approximations. For a one-domain crystal, the photonic bandgap is calculated in the regime of reflection along the 〈111〉 axis. In the multidomain case, a considerable expansion of the photonic bandgap, the emergence of asymmetry, and the photon band shift to the short-wavelength region are demonstrated. The results are compared with experimental dependences. 相似文献
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We observed a new effect which we called the photonic flame effect (PFE). Several three-dimensional photonic crystals (synthetic
opals) were posed on a Cu plate at the temperature of liquid nitrogen (77 K). The typical distance between the crystals was
1–5 cm. A long-continued optical luminescence was excited in one of the crystals by the ruby laser pulse. A visible luminescence
appeared in the other crystals (not illuminated by the laser pulse), with a time delay with respect to the luminescence in
the first crystal (illuminated by the laser pulse) being observed. We examined synthetic opal crystals and those filled with
nonlinear liquids. 相似文献
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Photonic crystal vertical cavity surface emitting lasers (PC VCSELs) are reviewed. The PC VCSEL shows single-transverse-mode continuous wave operation in the entire current range with side mode suppression ratio 35-40dB. A simple 3-D plane wave expansion method is found to be very effective in analyzing the modal properties of the PC VCSELs. 相似文献
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We demonstrated lasing in two-dimensional trivalent network structures with short-range order. Despite the lack of translational and rotational symmetries, such structures possess a large isotropic photonic bandgap. Different from those of a photonic crystal, the band-edge modes are spatially localized and have high quality factor. 相似文献
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基于光子晶体光纤Lyot-Sagnac环的可调谐微波光子滤波器 总被引:1,自引:0,他引:1
《光子学报》2015,(11)
提出了一种光子晶体光纤Lyot-Sagnac环切割宽带光源的中心频率连续可调的微波光子滤波器.用温敏液体(Cat.19340)对两段光子晶体光纤(长度为11.94m和1.94m)中心的一个大孔进行填充后嵌入Lyot-Sagnac环,仿真分析了不同填充占空比对Lyot-Sagnac环梳状谱周期和滤波器通带中心频率调谐范围的影响,结果表明:占空比越大,Lyot-Sagnac环的梳状谱周期越小,滤波器通带中心频率的调谐范围越大.在占空比最大温度为20℃和80℃时,两段光子晶体光纤的有效长度为10m时,LyotSagnac环的梳状谱周期分别为0.36nm和0.26nm;当两段光子晶体光纤的有效长度为13.88m时,Lyot-Sagnac环的梳状谱周期分别是0.26nm和0.19nm.用该Lyot-Sagnac环对宽带光源进行切割,当温度在20℃到80℃之间变化时,通过调节环内的偏振控制器,多波长光源波长间隔可在0.19nm~0.36nm范围内连续可调,实现了滤波器通带中心频率在31.04GHz~58.81GHz范围内连续可调. 相似文献
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Shao-Wei Wang Wei Lu Xiao-Shuang Chen Mei Zhou Xue-Chu Shen 《International Journal of Infrared and Millimeter Waves》2003,24(6):963-971
Photonic band gap (PBG) in two-dimensional (2D) anisotropic photonic crystal (PC) constructed of rectangular bars has been numerically studied by using Transfer Matrix Method (TMM). The results show that the PBG is bounded by the lower band edge of TE wave and the upper band edge of TM wave. Its width simply increases with increasing of shape parameter . It reaches a maximum value as the structure degenerates into its 1D counterpart, due to the complete overlapping of gaps in TE and TM waves. The anisotropy in PC structure results in the transmission anisotropic property. One can design the PBG structures in different incident directions to match their application demand. 相似文献