共查询到20条相似文献,搜索用时 31 毫秒
1.
A tunable double-channel filter is presented, which is based on a two-dimensional nonlinear ferroelectric photonic crystal made of cerium doped barium titanate. The filtering properties of the photonic crystal filter can be tuned by adjusting the defect structure or by a pump light. The influences of the structure disorders caused by the perturbations in the radius or the position of air holes on the filtering properties are also analyzed. 相似文献
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Fabrication of two-dimensional organic photonic crystal filter 总被引:1,自引:0,他引:1
A high quality two-dimensional photonic crystal filter made of polystyrene is fabricated by the method of focused ion beam
etching. Scanning electron microscopy (SEM) and transmittance spectrum are used to characterize the properties of photonic
crystal filter. The measured transmittance spectrum is in agreement with the theoretical one. It is found that the filtering
properties of photonic crystal filter, including the position and quality factor of optical channel, can be tuned by adjusting
the width of line defect.
PACS 42.70.Qs; 61.46.+w; 81.15.-z 相似文献
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A novel design of a tunable terahertz switch and band-pass filter using liquid-crystal-filled photonic crystal waveguide is demonstrated. The effects of magnetic field on the photonic bandgaps and transmitting properties of a THz wave are investigated by using the plane wave expansion method and finite difference time domain method. The efficient photonic bandgap tuning is predicted such that the two-dimensional liquid-crystal-filled photonie crystal waveguide can serve as a switch and continuously tunable band-pass filter with controlling of the magnetic field. 相似文献
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In this work, we theoretically analyze tunable filtering properties in a semiconductor-dielectric photonic crystal (SDPC) containing doped semiconductor defect in the mid-infrared frequency region. We consider two possible configurations of filter structures, the symmetric and asymmetric ones. With a defect of the doped n-type semiconductor, n-Si, the resonant transmission peak can be tuned by varying the doping concentration, that is, the peak wavelength will be shifted to the position of lower wavelength for both structures. Additionally, by increasing the defect thickness, it is also possible to have a filter with multiple resonant peaks, leading to a multichannel filter. The results provide another type of tunable filter in the defective SDPC that could be of technical use for semiconductor applications in optical electronics. 相似文献
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光子晶体多通道可调谐滤波器的理论研究 总被引:4,自引:1,他引:3
为了实现光子晶体的多通道滤波,对设计出的一维掺杂光子晶体进行了数值计算和理论分析。结果表明:多通道透射峰的波长与空气膜厚度呈线性变化,不同厚度的空气膜可以截到数目不同的透射峰,多通道透射峰的半高宽随光子晶体折射率n2的增加而减小。以此为基础,设计出滤波通道波长的可调范围达60nm,滤波通道半高宽的可调范围为1nm~5nm,滤波通道透射峰值大于0.98的一维光子晶体三通道可调谐滤波器。 相似文献
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This paper describes elaboration of two dimensional photonic crystal structures based on Thue–Morse sequence. Our results establish that the optical properties of these aperiodic multilayer systems can be tailored by adjusting either the radius of some cells of the proposed structure or defect characteristics. We introduce a resonant cavity in the proposed structure to select desirable wavelengths for filtering. Bandwidth of selected wavelengths are about 1 nm and suitable for communication applications. Also, our simulations show that efficiency of the proposed structure is enough. The total footprint of proposed filter is 331.24 μm2, therefore it is suitable to be integrated in all optical chips. 相似文献
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A new type of filter based on one-dimensional photonic crystals is presented. A photonic crystal consists of a periodic repetition
of air layers and epsilon-negative (ENG) material layers. This type of filter has high-Q values without defects. The Q values
and the filtering frequency can be precisely adjusted by modulating the thicknesses of the ENG material layers and the air
layers, respectively. A method of deciding the position of the transmission band for the photonic crystals is presented. The
effect of absorption of ENG materials on the filter is also considered.
PACS 42.70.Qs; 78.20.Ci; 41.20.Jb 相似文献
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铁电液晶缺陷光子晶体调谐滤波器的设计 总被引:2,自引:0,他引:2
将铁电液晶作为缺陷层引入一维光子晶体中,用电场改变液晶分子的取向,形成光子晶体快速可调谐滤波器.用传输矩阵法研究了铁电液晶缺陷光子晶体的可调谐滤波特性,计算了电压和液晶材料参量对滤波器透射谱的影响.结果表明:改变电压能容易改变光子晶体滤波器透射峰的位置、强度、个数和带宽,实现良好的调谐滤波功能. 相似文献
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Photonic crystal waveguide sampled gratings (PCWSG) are proposed to realize multi-channel optical filter in a photonic crystal (PC) waveguide. The reflection characteristics of the filter are analyzed by using the coupled-mode theory (CMT) together with transfer-matrix method (TMM). It is shown that the reflection spectrum of the filter exhibits a group of reflection peaks, which are distributed with equal frequency spacing within the photonic crystal bandgap (PBG). The theoretically calculated results are numerically verified by using two-dimensional (2D) finite-difference time-domain (FDTD) method. 相似文献
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本文提出一种采用石榴石型铁氧体磁性材料的太赫兹滤波器,利用波导线缺陷和腔内点缺陷的耦合特性,通过改变腔内介质柱半径及分布,实现对某个波长的耦合,达到了高效率滤波的功能;改变外磁场的大小,影响铁氧体材料的磁导率变化,使谐振频率发生改变,从而对THz波进行滤波.应用平面波展开法(PWM)和时域差分有限法(FDTD)进行仿真分析,研究结果表明,该滤波器其插入损耗为0.0997 d B,3 d B带宽为8.22 GHz,实现了低损耗窄带滤波. 相似文献
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为了研究1维光子晶体中光的全反射贯穿效应及其偏振滤波特性,利用传输矩阵法计算了TE波和TM波在大于全反射角入射1维光子晶体的透射率,发现在透射波中出现了全反射贯穿效应。研究了TE波和TM波的全反射贯穿效应随介质光学厚度和周期数的变化特征,表明:全反射贯穿峰的频率随介质光学厚度的增加而减少,全反射贯穿峰数与周期数相等。且全反射贯穿效应具有优良的偏振滤波特性,利用这些特性可以设计出结构简单、控制方便的1维光子晶体的偏振滤波器。 相似文献
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缺陷态复周期光子晶体的特性研究 总被引:8,自引:2,他引:6
利用传输矩阵法计算复周期结构的光子晶体的色散关系和滤波特性 ,并重点研究了含有缺陷的类似于谐振腔结构的光子晶体滤波特性.由于这种缺陷态复周期结构的可调参数多,人们很容易得到在红外波段1550 nm附近窄带滤波窗口,透过率可达到近90%,而窗口以外的透过率在0.02%以下.当改变中间夹层厚度、周期数及缺陷层数时,窄带滤波窗口的位置和带宽发生改变.因此,它在高速,长距离光通信中将有很好的应用. 相似文献
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The filtering properties for a narrowband reflection-and-transmission filter in an annular defective photonic crystal containing an ultrathin and strongly lossy metallic film are theoretically investigated based on the transfer matrix method for the cylindrical Bragg waves. At a certain design wavelength, simultaneous peaks in reflectance and transmittance can be found. The peak wavelength is shown to be dependent on the azimuthal mode number of the cylindrical waves. The peak heights in reflectance and transmittance can be directly varied by the stack numbers. In addition, the influence of the starting radius in reflectance and transmittance is also illustrated. 相似文献
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Tunable All-Optical Filtering and Buffering in a Coupled Quantum Dot-Planar Photonic Crystal Structure 下载免费PDF全文
We theoretically investigate controlled tunable all-optical filtering and buffering of optical pulses in a hybrid nano-photonic structure, where a single quantum dot (QD) embedded in a photonic crystal nanocavity is sidecoupled between a bare nanocavity and a photonic crystal waveguide. We demonstrate that there is a sharp low-loss transmission peak in the transmission spectrum under even low QD-nanocavity coupling strength and the input optical pulses can be delayed up to several hundred picoseconds within the dephasing time of the QD. The filtering regime can be shifted readily by manipulating the detuning between the QD excitonic transition frequency and resonant frequency of the nanocavity mode, which can be explored in future for on-chip all-optical logic and signal processing. 相似文献
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