共查询到19条相似文献,搜索用时 78 毫秒
1.
2.
本文报道1×N多通道声光偏转选址开关的研究.由 Ti 扩散 LiNbO3波导上两个短程透镜和一个倾斜 chirp 叉指换能器构成的集成光学声光偏转器,在两端分别对接一根和N根单模光纤时,用作多通道选址开关,在换能器带宽为200MHz,对1.3μm波长,可实现N=24;带宽增加到500MHz,可达到N=64,在波长为0.633μm的 He-Ne 激光下进行的实验和理论符合. 相似文献
3.
溶胶-凝胶TiO2和SiO2光学膜的结构 总被引:10,自引:4,他引:6
本文研究了TiO2和SiO2溶胶-凝胶光学膜在低温热处理下的组分、形貌特征、光散射特性.AES分析结果表明,在TiO2膜和SiO2膜的交界面处,Ti和Si相互扩散,从而证实了在多层膜中,膜层之间、膜层和基底之间有Ti-O-Si(或Si-O-Ti,或Si-O-Si)化学键形成.AES和ESCA分析结果显示溶胶-凝胶膜经过低温处理后C的含量较高,这归结为溶胶—凝胶膜的工艺特点.AFM测试结果显示,溶胶—凝胶TiO2光学膜的表面形貌具有显著的柱状结构,薄膜表面起伏大约是7.5nm.TiO2,SiO2单层膜的表面散射率随着热处理温度的提高而变大,对于不同陈化时间的溶液镀制的膜有不同的表面散率. 相似文献
4.
Thermal decomposition behaviors of TiH2 powder under a owing helium atmosphere and in a low vac- uum condition have been studied using an in situ EXAFS technique. By an EXAFS analysis containing the multiple scattering paths including H atoms, the changes of the hydrogen stoichiometric ratio and the phase transformation sequence are obtained. The results demonstrate that the initial decomposition temperature is dependent on experi- mental conditions, which occurs, respectively, at about 300 and 400℃ in a low vacuum condition and under a owing helium atmosphere. During the decomposition process of TiH2 in a low vacuum condition, the sample experiences a phase change process:δ(TiH2)→δ (TiHx)→δ(TiHx)+β(TiHx)→δ(TiHx)+β(TiHx)+α(Ti)→β(TiHx)+α(Ti)→α(Ti)+β(Ti). This study o ers a way to detect the structural information of hydrogen. A detailed discussion about the decomposition process of TiH2 is given in this paper. 相似文献
5.
高组份Al值的AlxGa1-x As和AlxGa1-x As/GaAs/AlxGa1-xAs/GaAs多层结构的MOCVD生长 总被引:1,自引:1,他引:0
用自制常压MOCVD系统,在半绝缘GaAs衬底上生长高Al组份AlxGa1-xAs(其x值达0.83),和AlxGa1-xAs/GaAs/AlxGa1-xAs/GaAs多层结构,表面镜面光亮。生长层厚度从几十到十几μm可控,测试表明外延层晶格结构完整,x值调节范围宽,非有意掺杂低,高纯GaAs外延层载流子浓度n300K=1.7×1015cm-3,n77K=1.4×1015cm-3,迁移率μ300K=5900cmcm2/V.S,μ77K=55500cm2/V.S。用电子探针,俄歇能谱仪测不出非有意掺杂的杂质,各层间界面清晰平直。 对GaAs,AlGaAs生长层表面缺陷,衬底偏角生长温度及其它生长条件也进行了初步探讨。 相似文献
6.
对于在流动干氩气中扩散而形成的Z-切Ti:LiNbO3平面波导,用Fouchet等人提出的钛感应折射率增量在0.6~1.6μm波长范围内的色散关系,推得与扩散参数有显函数关系的模式数量的色散公式。在若干重要波长,用这些色散公式,画出模式数量和扩散参数的关系曲线,可用来控制相应波导和器件的模式数量。 相似文献
7.
今年是集成光学诞生二十周年,本文就集成光学领域的进展与现状作一评述。重点介绍LiNbO3Ⅲ-Ⅴ族化合物半导体和硅衬底上的器件及其集成,工艺技术以及应用。 相似文献
8.
9.
10.
11.
一种定向耦合器型高聚物光开关设计 总被引:10,自引:10,他引:0
本文提出了一种基于定向耦合器型的高分子聚合物波导光开关设计,其突出特点是极低的波长相关性和耦合区几何尺寸敏感度,可采用橡胶成型工艺(Rubber Molding Process)实现高聚物波导在硅基底上的快速转印成型.利用BPM方法进行了器件的波导结构设计及性能模拟,插入损耗为0.4-0.6 dB,串扰<-32 dB,偏振相关损耗约为0.08 dB,电光系数r33=14 pm/V时,器件的开关电压为42 V. 相似文献
12.
A tunable wavelength filter is designed using Ti:LiNbO3 asymmetric directional coupler. One arm of the directional coupler is made of continuous waveguide while the other arm is periodic segmented. This segmentation reduces the lithographic steps and hence the fabrication cost required for such asymmetric coupler based filter. The propagation constant of periodical segmented and continuous waveguides are analysed using Effective-Index-based Matrix Method. The tunability is achieved using electro-optic property of LiNbO3. 相似文献
13.
A. A. Spikhal'skii 《Optical and Quantum Electronics》1986,18(2):103-114
Grating couplers for electro-optical diffused waveguides (such as Ti:LiNbO3, Ti:LiTaO3, etc.) are examined theoretically. A comparison of the improvements resulting from groove deepening, grating metallization, covering and multicovering of waveguide corrugation is made. Expressions for the calculation of the optimum parameters for multicovering are given and the method for optimization of the parameters is presented. It is shown that high-efficiency couplers for diffused electro-optical waveguides can be made using corrugations no longer than 1 mm and no deeper than 10 nm. A numerical illustration is presented to demonstrate the usefulness of the method for the improvement of other grating devices (distributed Bragg reflector, thin-film grating coupler). 相似文献
14.
We present a novel design and analysis of two nano-scale plasmonic devices: a directional coupler and a Mach–Zehnder interferometer. The designs of the two devices are based on our recent work on the air-gap coupler that resulted in high coupling efficiency between a dielectric waveguide and a plasmonic waveguide. The two devices are embedded between two dielectric waveguides and operate at optical telecom wavelengths. The overall efficiency was 37% for a 2×2 directional coupler switch and above 50% for the proposed designs for a Mach–Zehnder Interferometer. The efficiency in the proposed devices can be increased using broader plasmonic waveguides. 相似文献
15.
We analyzed the evolution of chirped optical pulses in a nonlinear directional coupler by coupled nonlinear Schrödinger equations. It is shown that an optical pulses launched into one channel can couple out from either of the two channels of the nonlinear directional coupler, with the routing determined by the chirp of the pulse. This is different from the previous routing mechanism of the nonlinear directional coupler where routing is determined by the peak power of the pulse. Based on the chirp-dependent feature, all-optical router and switch could be implemented by the pulse chirp modulation. 相似文献
16.
17.
18.
提出了一种简便可行的SOI无间距定向耦合光开关(BOA型-Bifurcation Optique Active)模型分析方法,采用等离子体色散效应这种光开关的电学调制机理;而用pn结大注入效应分析开拳电学性质;并根据大截面单模SOI脊形波导理论和上棕分析,设计了利用双模干淑机制工作的这种器件的结构参数和电学参数。 相似文献
19.
V. M. Kotov 《Technical Physics》1997,42(7):769-774
Planar acoustooptic 2×2 directional couplers that switch optical rays with different wavelengths are considered. A method
for calculating the angular and frequency characteristics of such switches is developed, and the parameters of a switch based
on a planar Ti-LiNbO3 structure are calculated. Experiments employing bulk acoustooptic diffraction in TeO2 are performed, confirming the basic theoretical assumptions. It is shown experimentally that the best conditions for switching
optical rays directed into optical fibers can be provided nearly always by varying the diffraction angles and the frequencies
of the sound waves. The functional possibilities of the 2×2 directional coupler investigated in a fiber-optic gyroscope are
described.
Zh. Tekh. Fiz. 67, 57–62 (July 1997) 相似文献