共查询到19条相似文献,搜索用时 156 毫秒
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提出了一种具有完全带隙的二维复式晶格光子晶体,该晶体是在二维正方形格子中,旋转截面为正方形的柱子,同时在每个原胞中心引入圆形截面的柱子而形成的,并在其中引入点缺陷。运用平面波展开法并结合超晶胞理论分析此缺陷态光子晶体的频率特性。仿真结果表明,通过调节缺陷的尺寸、角度等结构参量,可以改变缺陷态频率的位置,使TE和TM模缺陷态频率一致,TE模和TM模同时谐振,处于缺陷态频率的入射光就能够完全耦合进点缺陷,具有较高的耦合效率。这种结构的复式晶格完全带隙光子晶体为制作完全带隙光子晶体谐振腔提供了理论基础。 相似文献
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提出了一种新型的非对称性散射体的二维六角晶格光子晶体结构–-太极形介质柱光子晶体. 利用平面波展开法从理论研究这种光子晶体结构的能带特性以及结构参数对完全禁带的影响. 研究表明:散射体对称性的打破, TE模和TM模能带宽度和数目都会有所增加, 有益于获得更宽的完全禁带以及更多条完全禁带.通过参数优化, 发现在ε = 17, R=0.38 μm, r=0.36R, θ = 0° 时, 获得最大完全带隙宽度0.0541(ωa/2πc); 在ε = 16, R=0.44, r=0.2R, θ = 0°时, 光子晶体完全带隙数目最多达到8条.
关键词:
光子晶体
禁带
平面波展开 相似文献
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采用平面波展开的方法计算了正方格子二维磁性光子晶体(MPC)的光子带隙结构.散射子的形状分别为:长方形,正方形,六角形和圆形.通过调节磁导率,填充率和散射子的旋转角度,找到了MPC各种结构的最大的绝对带隙宽高比ωR.研究发现:随着磁导率的增加,MPC绝对带隙中心频率ωg单调减小,绝对带隙宽度Δω和其宽高比ωR可能不同时达到最大值.而随着填充率或者散射子旋转角的增加,基本不改变ωg的大小,各种结构的Δω和ωR同时达到最大值.
关键词:
磁性光子晶体
光子带隙结构 相似文献
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The polarization-dependent photonic band gaps (TM and TE polarizations) in two-dimensional photonic crystals with square lattices
composed of air holes in dielectric and vice versa i.e., dielectric rods in air, using the plane-wave expansion method are investigated. We then study, how the photonic band
gap size is affected by the changing ellipticity of the constituent air holes/dielectric rods. It is observed that the size
of the photonic band gap changes with changing ellipticity of the constituent air holes/dielectric rods. Further, it is reported,
how the photonic band gap size is affected by the change in the orientation of the constituent elliptical air holes/dielectric
rods in 2D photonic crystals. 相似文献
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采用平面波展开法数值计算了空气背景中由圆形、正六边形和正方形介质柱构造的二维三角晶格光子晶体禁带结构,并研究了介质方柱旋转角度、介质折射率和填充比对完全光子禁带宽度的影响.结果表明,在低频区,介质方柱旋转17°时,出现最大完全光子禁带,且最大禁带宽度随介质折射率的变化较为稳定.在高频区,介质方柱旋转30°时,完全光子禁带宽度最大;且介质材料折射率n=2.2时即出现完全光子禁带,n=2.6时,完全光子禁带达到最大. 相似文献
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Photonic band structures of two-dimensional photonic crystals with deformed lattices 总被引:2,自引:0,他引:2 下载免费PDF全文
Using the plane-wave expansion method, we have calculated and analysed the
changes of photonic band structures arising from two kinds of deformed
lattices, including the stretching and shrinking of lattices. The square
lattice with square air holes and the triangular lattice with circular air
holes are both studied. Calculated results show that the change of lattice
size in some special ranges can enlarge the band gap, which depends strongly
on the filling factor of air holes in photonic crystals; and besides, the
asymmetric band edges will appear with the broken symmetry of lattices. 相似文献
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In this paper, we investigate the existence and variation of complete photonic band gap size with the introduction of asymmetry
in the constituent dielectric rods with honeycomb lattices in two-dimensional photonic crystals (PhC) using the plane-wave
expansion (PWE) method. Two examples, one consisting of elliptical rods and the other comprising of rectangular rods in honeycomb
lattices are considered with a view to estimate the design parameters for maximizing the complete photonic band gap. Further,
it has been shown that complete photonic band gap size changes with the variation in the orientation angle of the constituent
dielectric rods.
相似文献
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L. F. Marsal T. Trifonov A. Rodríguez J. Pallars R. Alcubilla 《Physica E: Low-dimensional Systems and Nanostructures》2003,16(3-4):580
We investigate different aspects of the absolute photonic band gap (PBG) formation for two-dimensional photonic crystals, consisting of air rods drilled into silicon. Specifically, square lattices of square and circular rods are considered. The lattice symmetry, shape and orientation of the rods affect the photonic gap parameters. A symmetry reduction by addition of a smaller different shaped rod into the center of the lattice unit cell can produce significantly larger band gap. Combining the symmetry reduction and rotation of the noncircular rods yields the greatest improvements in the size of absolute band gap. We discuss the maximization of the absolute PBG width as a function of lattice parameters and the practical fabrication feasibility of these optimized structures. 相似文献
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