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把时域有限差分方法用于二维正方介质柱组成光子晶体传输函数理论研究,计算了若干情况下二维光子晶体的透射率即光传输函数随频率的变化。计算结果表明:对于一定的入射方向,某些频率的光不能在光子晶体中传播即出现所谓的禁带,禁带的宽度、频率范围与晶格结构、柱体截面大小及放置方位有关。 相似文献
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INTRODUCTIONInvestigationofphotonicbandgap(PBG)materialsiscurrentlyoneofthemostactivefron-tiersinengineeringandphysics.PBGmaterialshaverecentlyemergedasanewmultidisciplinaryfieldofstudy(Kesleretal.,1996;Yablonovitch,1994;SimovskiandHe,2001).APBGstructurecanhaveabandgapwithinwhichelectromagnetic(EM)wavepropagationispreventedinalldirec-tions(Joannopoulosetal.,1997;Ozbayetal.,1994).Foratwo-dimensionalPBGmaterial,thepropagationofanEMwavewithinitsbandgapispreventedinalldirectionswithin… 相似文献
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A new photonic bandgap (PBG) cover for a patch antenna with a photonic bandgap substrate is introduced. The plane wave expansion
method and the FDTD method were used to calculate such an antenna system. Numerical results for the input return loss, radiation
pattern, surface wave, and the directivity of the antennas are presented. A comparison between the conventional patch antenna
and the new PBG antenna is given. It is shown that the new PBG cover is very efficient for improving the radiation directivity.
The physical reasons for the improvement are also given.
Project supported by the National Natural Science Foundation of China (No. 90101024) and the Science and Technologies of Zhejiang
Provinc (No. ZD0002) 相似文献
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A novel defected ground structure （DGS） for the microstrip line is proposed in this paper. The DGS lattice has more defect parameters so that it can provide better performance than the conventional dumbbell-shaped DGS. Selectivity is improved by 97.2% with a sharpness factor of 24.6%. The method is applied to the design of a low-pass filter to confirm validity of the proposed DGS. 相似文献
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光子晶体是20世纪80年代末提出的新概念和新材料,迄今取得异常迅猛的发展,是一门正在蓬勃发 展的有前途的新学科.光子晶体不仅具有理论价值,更具有非常广阔的应用前景,这个领域已经成为国际学术 界的研究热点.本文介绍光子晶体的基本概念,理论研究方法以及应用前景. 相似文献
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* A defected ground structure (DGS), realized byetching defects in backside metal ground, is devel-oped froma photonic bandgap (PBG) structure. DGScan change the equivalentcircuitand therefore changethe transformation characteristic of a microstrip line. PBG structure is a kind of artificial crystal, inwhich one dielectric material arranges periodically inanother. This structure can prevent the propagation ofthe electromagnetic wave in a special frequency band.PBG structure has a verybroa… 相似文献
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A Novel Electromagnetic Bandgap Structure for Filter 总被引：1，自引：0，他引：1
Electromagnetic bandgap (EBG) materials are periodic structures capable of prohibiting the propagation of electromagnetic waves within a certain band of frequencies. This characteristic of EBG has wide application. The structures to be studied here are mainly planar EBG materials of two dimensions, which are periodic arrays of holes etched in the ground plane of a conventional microstrip line. EBG structures are calculated with finite-difference time-domain (FDTD) method in this paper. Technique of the perfectly matched layer is used for the absorption of electromagnetic waves in FDTD. The FDTD method is programmed with the blend of C^ and Matlab languages, which makes the program both simple and fast computing. A kind of new EBG structure is brought out through a lot of experiments and analyses. A filter with wide stop-band and another filter with two stop-bands are designed. 相似文献
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张晓娟 《渭南师范学院学报》2012,(12):37-40
运用平面波法研究了光波由面内入射到二维正方晶格光子晶体时的光子带隙,详细讨论了原子半径、原子介电常数及引入不同结构缺陷对光子晶体光子带隙的影响.结果表明:设置不同的原子半径和介电常数,可以得到不同波长范围的光子带隙;引入不同的缺陷结构,可以在禁带中形成不同频率的通带.因此,为了使不同波长的光波通过,可以在光子晶体中引入不同类型的缺陷. 相似文献
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