共查询到19条相似文献,搜索用时 109 毫秒
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实验验证了室温下二维氧化物下包层非对称平板三角晶格光子晶体渐变型双异构微腔对绝缘体上硅(SOI)基片上铒氧共掺硅材料的显著发光增强作用.在波长为488 nm、功率为15 mW激光激发下,微腔的光致发光(PL)谱呈现出一个位于1 557.93 nm通信波长处的尖锐狭窄的发光峰,相比于无光子晶体区域,发光增强了约13倍.谐振峰随光泵浦功率增加,发生明显的红移,Q值逐渐下降,在1.5mW光泵浦功率下,Q值达6 655.微腔谐振波长与光子晶体晶格周期之间呈线性正比关系,通过调整晶格周期,实现了掺铒硅发光增强峰波长的灵活可控. 相似文献
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二维光子晶体耦合腔的多模双稳态光开关 总被引:2,自引:1,他引:1
利用时域有限差分数值模拟方法和耦合模理论分析方法,研究了Kerr型非线性二维光子晶体耦合腔结构中的光学双稳态开关。利用耦合模理论,分析了耦合腔结构的多模特性,以及对应本征态的局域强度分布特性,并讨论了在耦合腔结构中实现多模光学双稳态开关的原理。发现在二维耦合腔结构中,可以实现信号自泵浦和泵浦-信号两种类型的双稳态开关,且后者具有使泵浦和信号在频率和空间相分离的优点。利用非线性时域有限差分数值模拟方法,得到了高斯脉冲激励下的双稳态响应曲线。 相似文献
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用时域有限差分法和介质的等效折射率概念,研究了三角形结构的等效负折射率光子晶体的透射谱,研究发现选择合适的波源的工作频率,在等效负折射率光子晶体中,因Bloch波共振和受激辐射以及光子隧道贯穿极大地增强了自发辐射的几率,使能量被高度局域,进而大大增强了它们的透射率,从而获得明显的全光开关效应,进一步研究发现当二维光子晶体三角形结构的圆柱空气孔改为椭圆柱空气孔时,椭圆孔激发对应的透射峰远大于圆柱空气对应的透射峰,即椭圆孔具有很高的品质因数,从而形成性能极优的光开关效应,有望在实现高效光放大、光子晶体激光器和全光开关等方面得到广泛的应用。 相似文献
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光子晶体是介质介电常数呈周期性排布的结构,具有光子带隙,处于光子带隙中的电磁波无法在其中传播。二维平板光子晶体是通过在衬底上刻蚀周期性排列的空气孔柱而形成的结构,由于其具有优良的控制光传播的特性而得到广泛的研究和应用。介绍了在二维平板光子晶体中引入缺陷形成的光子晶体微腔和波导的方法和性质。通过调整几何参数控制微腔与波导之间的耦合,实现基于二维平板光子晶体的全光开关、光存储、单光子源等光学器件并讨论其在量子光学网络中的应用。 相似文献
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光子晶体中光传播特性研究是物理学研究的前沿热点之一。近年来,以共振吸收或放大介质的周期排列所形成的共振激活光子晶体的研究不断见诸报道。此类光子晶体的特点是,该晶体的折射率之差是由周期排列的原子在共振吸收峰附近的剧烈色散相干叠加所提供,它除了表现出类似被动周期结构的光子带隙外,还具有由于原子和激子的层间耦合导致的能级移动、吸收的布拉格压缩以及光学开关特性等。我们的数值模拟表明:利用超短激光脉冲可激发-维共振结构的禁带光孤子,光子可减速、存储与受控释放;零速超短脉冲还可以增强受激拉曼散射效率。 相似文献
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柚子型光子晶体光纤布拉格光栅理论及实验研究 总被引:2,自引:0,他引:2
利用有限元法对一种柚子型光子晶体光纤中的传输模式进行了模拟,得到了各传输模式的有效折射率和模场分布。结合耦合模理论和相关函数方法,对柚子型光子晶体光纤布拉格光栅反射谱进行了理论分析,解释了柚子型光纤光栅出现多个谐振峰的原因;数值分析了光纤纤芯直径和空气孔尺寸对光栅传输谱的影响。结果表明谐振峰波长随纤芯直径的增大向长波方向漂移,而随空气孔增大向短波方向移动,并且不同谐振模式的变化幅度不同;利用相位模板法写制了光子晶体光纤光栅,实验结果与理论分析能够很好地吻合。 相似文献
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Sugimoto Y. Ikeda N. Carlsson N. Asakawa K. Kawai N. Inoue K. 《Quantum Electronics, IEEE Journal of》2002,38(7):760-769
An AlGaAs-based near-infrared 2-D photonic crystal (PC) with an air-bridge structure featuring defect waveguides has been developed. For the sample without defect waveguides, measurements of the optical transmission characteristics in the wavelength range from 850 nm to 1100 nm showed a deep attenuation due to a bandgap with 30-35 dB attenuation and transmittance of nearly 100% for the guided modes. Optical propagation properties of defect waveguides were obtained by two methods: measurements of transmission spectra and plan-view observations of the optical beam trace along the waveguide with an infrared-vidicon camera. 3-D finite-difference time-domain simulations for the band structure and transmission spectra in the air-bridge slab with and without defect waveguides have revealed the appearance of four defect propagation modes specific to the defect waveguide, between two slab modes for the defect-free photonic crystal slab. These defect modes were experimentally identified in the measured transmission spectra 相似文献
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Shimada R. Yablonskii A.L. Tikhodeev S.G. Ishihara T. 《Quantum Electronics, IEEE Journal of》2002,38(7):872-879
The transmission properties of a 2-D photonic crystal slab with an exciton resonance are investigated experimentally and theoretically. Good agreement between experiment and scattering matrix based theory is obtained. The photonic crystal slab is composed of a square lattice of etched square holes in a quartz substrate, filled by an inorganic-organic semiconductor and covered by a polystyrene guiding film. We demonstrate that the transmissivity of the structure shows pronounced dips, which originate from the excitation of quasi-guided modes in the photonic crystal slab. The measured and calculated angular dependence of the energy of these dips and their optical activity allow us to identify the physical properties of the quasi-guided modes, such as their symmetry and distribution of electromagnetic field 相似文献
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Imada M. Noda S. Chutinan A. Mochizuki M. Tanaka T. 《Lightwave Technology, Journal of》2002,20(5):873-878
This paper describes a theoretical and experimental analysis of the channel drop filter using a single defect formed near the two-dimensional (2-D) photonic crystal slab waveguide. First, we calculate the transmission spectrum of a 2-D photonic crystal waveguide and show that high transmittance for a wide wavelength range (/spl sim/60 nm) is obtained in the 1.55-/spl mu/m region. We also show that a defect state having a wavelength within the high transmission wavelength range can be formed in the photonic bandgap by introducing a single defect of appropriate radius. Next, we fabricate several devices and show that the emission wavelength from each defect can be tuned by changing the defect radius. The measured tuning characteristics coincide well with the calculated results. From the near-field pattern of the device, we estimate the emission efficiency of the present device at almost a few tens percent. We clarify the structural condition in order to obtain the maximum output efficiency and show that tuning of emission wavelength while maintaining high output efficiency is possible by selecting appropriate defect radius and position. Based on these results, we propose an ultrasmall channel drop filter for a wavelength-division-multiplex optical communication system. 相似文献
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在二维光子晶体结构中通过调节光子晶体方形谐振器PCSRs(Photonic Crystal Square Resonators)与波导的耦合长度、耦合宽度、及其耦合柱半径优化设计了光信号分离器.借助于CMT(Coupled-Mode Theory)理论定性分析了两个PCSRs存在相互作用时,结构中波导与谐振腔之间的电磁波耦合性能,用FDTD方法研究了两信道传输工作特性.表明在设计的参数范围中,基于PCSRs的信号分离器具有高正规化传输率、窄带宽、平稳的信号传输强度,中心波长调谐范围宽的特性.该类结构可用于同一中心波长信号的功率二等均分,也可用于不同中心波长信号的分离.该微型结构在片上的光路设计将是一类有潜力的构筑模块,适于光通信领域波分解复用设计、光路集成设计等方面. 相似文献
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用时域有限差分法(FDTD)分析了二维光子晶体的传输特性,研究了纯平面波源、高斯波源对传输特性的影响,指出在同一种激励源情况,二维光子晶体的传输特性与其入射角有关。 相似文献
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Zimmermann J. Kamp M. Schwertberger R. Reithmaier J.P. Forchel A. Marz R. 《Electronics letters》2002,38(4):178-180
Very efficient light transmission over a length of several millimetres through linear photonic crystal slab waveguides, patterned into an InGaAlAs waveguiding layer on InP substrate, is demonstrated. Quantitative evaluation of the light propagation in these waveguides, using the Fabry-Perot resonance method, yields a minimum loss of 1.6 dB/mm, for a waveguide with seven missing rows at 1550 nm wavelength 相似文献
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Reynolds A.L. Chong H.M.H. Thayne I.G. Arnold J.M. De Maagt P. 《Microwave Theory and Techniques》2001,49(7):1254-1261
The study of the transmission of electromagnetic waves through a photonic crystal with various membranes placed over the surface is presented in this paper. A difference in performance is observed even for a membrane thickness that is unable to support guided substrate modes through total internal reflection. The transmittance has been investigated for two crystal orientations, assuming normally incident external plane waves on a finite thickness two-dimensional (2-D) photonic crystals both with and without a membrane. The angular transmission response is characterized by scanning the incidence angle of the impinging plane wave to cover all available angles within the 2D periodic plane of the structure 相似文献
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建立了(AB)N型一维光子晶体结构多通道可调谐滤波器模型,其中A层是砷化镓(GaAs)材料,B层是由掺铝的氧化锌层和氧化锌层(AZO/ZnO)交替排列构成的具有人工周期结构的各项异性材料。根据电磁波的传输矩阵理论,推导了光子晶体的透射率公式。数值模拟表明:此结构光子晶体透射中心波长是1.55 m,对应于光子通带;透射峰的数量由光子晶体的周期N决定;B层中填充因子h从2/3增加到11/12,峰值波长蓝移且移动范围超过200 nm;A和B层厚度增加,透射峰中心波长发生红移;而入射角度的增加将使透射峰中心波长蓝移;在各参数的调控范围内,光子晶体均保持较高的透射率不变。这些现象为光通信波段多通道可调谐高性能滤波器的设计提供了理论参考。 相似文献