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采用Si和SiO2两种介质材料构造一维缺陷光子晶体,缺陷层介质为Si,利用传输矩阵法对带有缺陷的一维光子晶体的传光特性进行了理论分析,并得到其带隙特性.由于缺陷的存在,使得光子晶体的透射谱中产生缺陷峰.当被测温度变化时,根据两种介质的热光效应和热膨胀效应,光子晶体介质和缺陷层的光学厚度和折射率发生变化,透射谱缺陷峰产生漂移,由缺陷峰的中心波长漂移量得到被测温度的大小.构建了一维缺陷光子晶体测量温度的实验系统,实验结果表明缺陷峰中心波长与光子晶体所受的温度呈线性关系,测量灵敏度为0—2 相似文献
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为了在可见及近红外波段得到具有良好带隙结构的三维光子晶体,利用传输矩阵法分析了MgF2、Ta2O5 以及Ta2O5/MgF2异质结构三维光子晶体的带隙性质.结果表明:Ta2O5/MgF2异质结构三维光子晶体在820~1 020 nm的近红外波段TM模式下具有不受入射光方向影响的全方位光子带隙.该结构有望用于制作近红外光波段的偏振器件. 相似文献
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研究了阶梯型折射率n22、n11(阶梯分布高度)的大小、对应的分布厚度、不同入射角以及缺陷模对阶梯函数型光子晶体透射特性的影响.由费马原理给出光在函数光子晶体中的运动方程,再由电磁传播理论给出函数光子晶体的传输矩阵,进一步推导出函数光子晶体的透射率以及电场分布的表达式.研究表明,1)随n22,n11大小或者厚度改变,其禁带变宽;2)随光的入射角增加,其禁带变窄;3)当加入缺陷层时,随着缺陷层介质折射率增加,缺陷模强度减小且位置发生红移;4)在函数光子晶体中,缺陷层前电场分布保持不变,而在缺陷层处以及之后的电场强度都明显增强,这不同于常规光子晶体的电场分布仅在缺陷层处局域增强. 相似文献
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构造了由普通材料A(SiO2)和电单负材料B组成的(AB)N(BA)N型一维光子晶体.数值计算表明原禁带的1907.3 nm处出现了一个十分尖锐的隧穿模. 入射角增加,该隧穿模的透射率和半峰全宽度均保持不变,但位置发生蓝移, 入射角在15°-65°的区间内,移动率的绝对值 |dλ/dθ| 较大.当B介质的磁导率μB 从5增加到10时,只是隧穿模的位置发生了红移. 介质的几何厚度增加时,隧穿模的透射率不变,但其位置红移明显,半峰全宽略有增加. 相似文献
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基于平面波展开法,设计三层一维光子晶体横磁场模结构,改变三层介质厚度和介质折射率的大小,应用MATLAB语言进行仿真计算,在一维光子晶体三层介质厚度值为0.4、0.05μm和0.05μm,折射率为1、3N和12N时形成一维光子晶体带隙宽度最宽为0.2694Hz.研究结论为一维光子晶体器件的设计提供理论依据. 相似文献
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基于平面波展开法,设计九层一维光子晶体结构,通过改变结构中介质层的厚度,运用MATLAB编程计算一维光子晶体反射率特性,厚度差值变小时,不存在反射波的区域将增加变大。研究结果为一维光子晶体器件的设计提供理论参考。 相似文献
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Quantum electrodynamics of atom spontaneous emission from a three-dimensional photonic crystal is studied in a full vectorial framework. The electromagnetic fields are quantized via solving the eigenproblem of photonic crystals with use of a plane-wave expansion method. It is found that the photon density of states and local density of states (LDOS) with a full band gap vary slowly near the edge of band gap, in significant contrast to the singular character predicted by the previous isotropic model. Therefore, the spontaneous emission can be solved by conventional Weisskopf-Wigner approximate theory, which yields a pure exponentially decaying behavior with a rate proportional to the LDOS. 相似文献
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报道了一种新型的利用激光全息技术制作光子晶体的记录材料,即自制的非水溶性光致聚合物.用绿光作为光源对材料性能参量做简单测试,经测试其衍射效率可达85%,在波长为514.5 nm处拥有较高的吸收率,且该材料的后处理过程简单,只需热烘.利用Matlab简单模拟全息法制作光子晶体的过程,经模拟得到干涉的光束越多,光子晶体的晶格结构越复杂.设计了制作二维、三维光子晶体的实验光路,分光元件分别为掩模板和去顶棱镜.实验结果表明,利用非水溶性光致聚合物可制作大面积、大体积、耐高温和高强度的二、三维光子晶体,且其晶体结构与Matlab模拟的结果基本一致|利用非水溶性光致聚合物作为记录材料时,光路的搭建是影响实验结果的重要因素. 相似文献
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E. V. Astrova V. A. Tolmachev G. V. Fedulova V. A. Melnikov T. S. Perova 《Bulletin of the Russian Academy of Sciences: Physics》2010,74(1):65-68
The formation of periodic wall arrays on an n-type (100) Si substrate with V-shaped seed grooves on the surface was investigated. The influence of silicon sidewall roughness
on the optical properties of onedimensional (1D) of photonic crystals obtained on the basis of the arrays was studied. The
reflection spectra of the 1D photonic crystals exhibit a high modulation level of up to 95% and photonic band gaps of a high
order that are in good agreement with calculations over a wide spectral range (1.5—15 μm). 相似文献
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A detailed study of a platform of ultra-small photonic large-scale integrated circuits was conducted. Bandgap structure calculations of silicon-on-insulator (SOI) based photonic crystals have been investigated. The photonic crystal consists of dielectric cylinders in air. Using the band structure calculations we obtained design parameters for the proposed structures. The coupling between the photonic crystal and a waveguide fabricated from SOI system has been analysed. It is shown that the optical coupling is improved by interfacing different types of spot-size converters (SSCs) between the SOI waveguide and the photonic crystal. Also, the possibility and limitations of silicon doped germanium and SOI photonic crystals to analyse the light guiding in the third dimension is discussed. 相似文献
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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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J. Kh. Nurligareev 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2011,5(1):193-208
Floquet-Bloch waves in a bound one-dimensional photonic crystal are considered. It is shown that a single Floquet-Bloch wave
can be excited in a one-dimensional photonic crystal located between two homogeneous media. An exact solution of the wave
equation corresponding to this case is represented in the form of a set of heterogeneous waves. For the case of incidence
of the plane wave from a homogeneous medium on a bounded one-dimensional photonic crystal, the functions for the reflection
and transmission coefficients are obtained based on the exact solution of the wave equation. It is shown that the transmission
function for the one-dimensional photonic crystal has a form similar to that for the traditional Fabri-Perot interferometer
and is determined by the interference of the Floquet-Bloch waves excited in the crystal. The evolution of the amplitude profile
of the decaying Floquet-Bloch waves and the reflection spectrum of the bounded one-dimensional photonic crystal are considered
in the first-order forbidden band. 相似文献
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具有复介电常量二维光子晶体的特性研究 总被引:6,自引:0,他引:6
采用平面波展开法,通过数值模拟研究了具有复介电常量的二维光子晶体的能带结构和光传输特性,重点讨论介电常量的虚部为负值情形时对传输特性的影响。研究表明由于光子带隙的存在有效地抑制了频率位于带隙内光的自发辐射。当在介质中掺入具有增益特性的杂质时,即使两种介质的介电常量相差很小,在靠近光子带隙边缘,出现了较强的受激辐射放大。通常在带隙的边缘处,光子晶体的群速度较小,而激光阈值正比于群速度的平方,当群速度很小时,激光阈值将大大减小。这为实现零阈值激光器提供了基础,也为制作光放大微器件提供了一个有益的理论参考。 相似文献