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利用传输矩阵法研究了正负折射率材料构成的异质结构光子晶体的光学传输特性。结果表明:当入射波正入射时,在这种异质结构光子晶体内出现了光子带隙,并且带隙内出现了3个极窄的透射峰,这是正负交替光子晶体和常规材料构成的同周期一维异质结构光子晶体所不具有的新颖物理特性。计算了这种异质结构光子晶体的透射谱。发现:这3个透射峰不敏感于入射角的变化,而在带隙两侧的透射峰则会随着入射角增大统一向带隙靠近;能带敏感于晶格厚度和周期数的变化。 相似文献
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利用传输矩阵法研究了含特异材料的一维超导光子晶体的带隙特性. 研究表明, 这类超导光子晶体同样具有由传统的电介质材料构成的超导光子晶体一样的低频带隙, 且在一定的参数下该低频带隙可以相当宽. 但在一定的结构参数下, 这类超导光子晶体同完全由传统的电介质构成的光子晶体一样不存在低频带隙. 还就超导光子晶体的偏振特性、光子晶体结构参数及环境温度的变化对光子带隙结构的影响进行了研究.
关键词:
超导光子晶体
传输矩阵法
特异材料
光子带隙 相似文献
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含负折射率材料的一维光子晶体的光学传输特性 总被引:12,自引:2,他引:10
采用光学传输矩阵方法,模拟研究了由正折射率材料和负折射率材料交替组成的一维光子晶体的光学传输特性.计算了这种含负折射率材料的一维光子晶体的透射谱和色散关系.结果表明,在正入射时,含负折射率材料的光子晶体的带隙要比传统的光子晶体要大得多,并具有狭窄的透射带,从光学薄膜理论的色散关系出发解释了形成上述现象的原因.讨论了在不同的偏振模式下,光以中心波长入射时,反射率随着入射角度的变化关系.发现含负折射率材料的一维光子晶体具有更好的角度特性,可以用来实现对中心波长的全方位反射. 相似文献
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《中国光学与应用光学文摘》2005,(4)
O734 2005043065 含负折射率材料的一维光子晶体的光学传输特性= Transmission properties of one-dimensional photonic crys- tals containing negative refraction materials[刊,中]/尹承平(南昌大学物理系,江西,南昌(330047)),刘念华//发光学报,-2005,26(2),-173-177 采用光学传输矩阵方法,模拟研究了由正折射率材料和负折射率材料交替组成的一维光子晶体的光学传输特性,计算了这种含负折射率材料的一维光子晶体的透射谱和色散关系。结果表明,在正入射时,含负折射率材料的光子晶体的带隙要比传统的光子晶体大得多,并具有狭窄的透射带,从光学薄膜理论的色散关系出发解释了形成上述现象的原因。讨论了在不同的偏振模式下,光以中心波 相似文献
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二维正方晶格光子晶体禁带特性 总被引:3,自引:3,他引:0
基于平面波展开法,以碳化硅构成二维正方晶格光子晶体,数值模拟了TE模、TM模二维光子晶体的禁带特性,结果表明,TE模更容易形成光子禁带。同时设计了以碳化硅构成二维正方晶格光子晶体波导,数值模拟了TE模、TM模波导的传输特性和禁带特性,结果表明,TE模构成的波导电磁波能够较好的传播,它们的光子禁带都没有出现。研究结论为光子晶体波导器件的开发提供参考。 相似文献
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与介质柱型光子晶体相比,空气孔光子晶体更易于制作和集成而更有应用价值.采用平面波展开法证实了填充液晶的二维三角形分布的空气孔光子晶体方向能隙的可调节性.数值模拟结果表明:1)通过外界电场控制空气孔中所填充的相列液晶的方向可以对光子晶体的方向能隙进行调节,这种可调节性可用于制作场敏偏光片.这与Liu等人研究介质柱型光子晶体的结论相类似;2)用phenylacetylene型液晶替代5CB液晶作为填充物质所得到的空气孔光子晶体偏光片可使用的频率范围显著增大.在此基础上,还研究了填充液晶的光子晶体波导传输谱线的可调节性对特定波长的光切断和开通控制的原理,实现了与以往光开关原理不同的光子晶体光开关.
关键词:
光子晶体
液晶
可调节性
平面波展开法
场敏偏光片 相似文献
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《Photonics and Nanostructures》2014,12(1):75-82
In this paper, we investigate coupling of light to slow modes in a photonic crystal power splitter composed of a Y-junction and two 60° bends. First, a combination of two cascaded bends which is commonly used in integrated photonic crystal circuits is studied in slow light frequency regime. We propose a structure that its transmission spectrum covers the high group-index frequencies near the band edge. Also, by structural modifications, high transmission near to 95% is achieved in slow light bandwidth. Next, we study the complete structure of a photonic crystal power splitter with parallel outputs based on a Y-junction integrated with two 60° bends. Using modified bends and reducing sharpness of Y-junction, the efficiency of splitting increases in both high and low group-index frequency bands. The optimized structure has an average efficiency of 82% in slow mode regime. This structure can be used in photonic crystal based slow light devices, such as Mach-Zehnder interferometers. 相似文献
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一维金属/介质光子晶体用于BaF2晶体闪烁光谱修饰 总被引:14,自引:6,他引:8
利用一维金属/介质光子晶体对BaF2晶体闪烁光谱进行修饰. 以Al2O3/MgF2/Al/ MgF2为周期构成光子晶体,讨论了周期数、金属层的厚度以及在低折射率层中的相对位置、入射角度等与光子晶体能带特性的关系及其对BaF2晶体闪烁光谱进行修饰的效果. 结果表明,在所考虑的发射角范围,光子晶体对快成分的衰减小于5倍,对慢成分的相对抑制比超过20倍,采用合适的探测角度,可使对慢成分的相对抑制比提高到100以上. 相似文献
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《Current Applied Physics》2020,20(8):961-966
In this paper, a plasma photonic crystal (PPC) for infrared radiation modulation which is composed of indium tin oxide (ITO) and plasma is proposed. The performance of plasma photonic crystal in near infrared radiation modulation is researched by transfer matrix method (TMM). The simulation results show that the near infrared radiation pass band can be adjusted by the changing of plasma frequency of plasma. The reflection to near infrared radiation by plasma photonic crystal increases with plasma frequency and that of absorption decreases. In addition, the modulation performance of the plasma photonic crystal at different incidence wave angles is also studied. The results show that the incident wave angles have little effect on the transmission of plasma photonic crystal in near infrared band. The reflection of the plasma photonic crystal to near infrared radiation decreases with increasing of the incident wave angle, but that of the absorption increases with the incident wave angle. Therefore, the proposed plasma photonic crystal has a potential application in tunable near infrared filter devices. 相似文献
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光子晶体中缺陷的色散导致的群速度降低 总被引:8,自引:4,他引:4
利用传输矩阵方法计算了包含色散媒质缺陷的一维光子晶体的复透射系数,其中色散媒质用洛仑兹振子模型描述。计算了由复透射系数定义的等效复折射率并由此研究了频谱位于缺陷模频率附近的光脉冲的群速度。结果发现,由于缺陷模附近的透射谱敏感地依赖于缺陷层的光学厚度,而缺陷层的色散使缺陷层光学厚度随频率变化而改变,从而使包含缺陷的光子晶体的等效色散性质明显地依赖于缺陷的色散行为。由于光脉冲是由多种频率成分的单色场迭加构成的,透射脉冲由各单色场透射后重新迭加构成,因此波包的传播由介质的等效色散性质决定。与包含无色散缺陷的光子晶体相比,缺陷的色散可导致极慢的群速度。通过改变振子强度,群速度可从极慢光速转变为超光速(superluminal)。 相似文献
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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
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We investigated the optical properties of a circular photonic crystal (CPC) for which the distance between lattices was systematically distributed. The transmission spectra of CPC composed of alumina cylinders were examined in the frequency region from 0 to 20 GHz. We show that photonic gaps are obtained not only in CPCs but also in phase-shifted CPCs. The isotropic photonic gaps are evidenced by changes in the incident angle of a millimeter wave. 相似文献
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Fabrication of Colloidal Photonic Crystals with Heterostructure by Spin-Coating Method 总被引:1,自引:0,他引:1 下载免费PDF全文
Colloidal photonic crystal heterostructures, composed of two opaline photonic crystal films of silica spheres with different diameters, are fabricated by a two-step spin-coating method. Scanning electron microscopy (SEM) and UV-vis spectrophotometer are used to characterize the heterostructures. The SEM images show good ordering of the two-layer colloidal crystals constituting the heterostructures. The transmission spectra measured from the (111) plane in the heterostructure show that the composite colloidal photonic crystals have double photonic stop bands. Furthermore, when the sizes of the silica spheres used for fabricating the composite photonic crystal are slightly different, the transmission spectrum shows that the composite photonic crystals have more extended bandgap than that of the individual photonic crystals due to partial overlapping of its two photonic stop bands. 相似文献
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In this paper, the wave transmission from finite photonic crystals with multiple alternations is investigated using boundary element method (BEM). Since that, in these structures the alternation is not in all directions of space; the investigations of the frequency band gap with desired accuracy are not practical by analytical methods. Also, the frequency dispersion of dielectric rods is an effective parameter in photonic crystals, which this effect in our calculations has been considered. Due to the high capabilities of the BEM, the transmitted wave spectrum in the photonic crystal is calculated by changing the geometrical and optical parameters of the photonic crystal and applying more alternation in its structure and the position and width of the frequency band gap is investigated. Then, it is assumed that the photonic crystal with an arbitrary angle is rotated around the axis which is perpendicular on the crystal cross section and then, it is irradiated with a plan wave. The band gap of the photonic crystals with the desired structure, desired rotation angle and multiple alternations have been solved. Very low information volume, high speed and accuracy during the calculation and useable for any desired structures are the characteristics of this method. 相似文献