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101.
Optical and Electrical Properties of Ferroelectric SBN Thin Films Prepared by Sol-Gel Process 总被引:1,自引:0,他引:1
Junmo Koo Jae Hyeok Jang Byeong-Soo Bae 《Journal of Sol-Gel Science and Technology》2000,19(1-3):611-614
Strontium barium niobate thin films were prepared by sol-gel method on various substrates using an improved process, two-step heating process. The two-step heating process applies an additive heat-treatment before crystallization for enhancement of the densification and the nucleation of films. Also, highly c-axis oriented SBN thin films with various compositions were obtained on MgO(100) and Pt(100)/MgO(100) substrates. Their optical and electrical properties such as optical propagation loss, refractive index, P-E hysteresis, and dielectric constant, were characterized as a function of the film composition. 相似文献
102.
Matteo A.M. Tallone L. Boidi C. Cognolato L. Pozzi F. 《Optical and Quantum Electronics》2000,32(6-8):981-990
We present a semi-analytical modeling suitable for the investigation of the spectral characteristics of UV-waveguide Bragg gratings (UV-WBGs) having arbitrary apodization function and extending both in the film layer and in the overlayer. The modeling is based on a proper combination of coupled mode theory and transfer matrix formalism and provides a powerful tool for designing and simulation of complex UV-grating based structures. The results of a detailed investigation of UV-WBGs in doped silica based channel optical waveguides are presented and critical issues for upgrading the performances of related device are discussed. Validation of the modeling is provided by means of an extensive comparison between theoretical and experimental results relevant to UV-WBGs realized in phosphorous (P)- and boron (B)-doped silica based waveguides. 相似文献
103.
Shi-Chang Zhang 《International Journal of Infrared and Millimeter Waves》1986,7(6):869-880
A coaxial waveguide gyro-peniotron with largeorbit beam is proposed. The linear thoery of 3-D model is given to describe this device. The influences of the beam radius and beam current on the normalized growth rate are discussed in terms of numerical analysis. 相似文献
104.
脊形波导中导模传输与损耗的分析与计算 总被引:1,自引:0,他引:1
本文运用有效折射率法把脊形波导化成等效二维平板波导后,再运用微分法求出弱吸收情况下波导模的吸收损耗,其方法简便,精确度高. 相似文献
105.
Successful demonstration of selective area doping of planar glass samples for monolithic integration of optically passive and active devices on a single chip is presented. Salt solution of erbium was delivered onto pre-sintered germano-silicate samples via a syringe. The samples were then consolidated to form dense glass layers containing regions doped with rare earth. Erbium tri-chloride solution, 0.1 M, was used during the solution doping phase, with the resulting erbium atomic percentage ranging from more than 0.1-0.4%, increasing linearly with the number of drips applied. 相似文献
106.
Analysis for Transmission Characteristics of Closed Trapezoidal-Groove Waveguide with Boundary Element Method 总被引:1,自引:0,他引:1
Fuyong Xu Xiaohui Lin Bin You 《International Journal of Infrared and Millimeter Waves》1999,20(9):1691-1699
In this paper, the cut-off and dispersion characteristics of a new kind of closed trapezoidal-groove waveguide that has more advantages than open groove waveguides are analyzed with the help of the boundary element method, the relationship between cut-off wavelengths and variations of guide's relative sizes is discussed in detail. The calculated results are in good agreement with those in the relevant reference. So, the obtained conclusions are very important in theoretical studies and actual applications of closed trapezoidal-groove waveguides for millimeter and submillimeter waves. 相似文献
107.
Crosstalks of two-waveguide and three-waveguide directional couplers are analyzed mathematically based on the relationship between the coupled mode and the normal mode. Numerical techniques such as the finite-difference method and the beam propagation method are employed to confirm the validity of the derived expressions. The calculation results show that two-waveguide directional coupler is superior to any type of three-waveguide couplers from the practical viewpoint of the crosstalk and the coupling length. 相似文献
108.
Analysis of Ti:LiNbO3 zero-gap directional coupler for wavelength division multiplexer/demultiplexer
Pranabendu Ganguly Juran Chandra Biswas Samir Kumar Lahiri 《Optics Communications》2008,281(12):3269-3274
For the purpose of multichannel integrated-optical wavelength division MUX/DEMUX design, the wavelength tuning method of Ti:LiNbO3 zero-gap directional coupler is analysed by effective-index based matrix method (EIMM). In this method, first, the 2D refractive index profile of the Ti:LiNbO3 zero-gap directional coupler is transformed into lateral 1D effective-index profile by WKB method. Finally, matrix method is applied to this effective-index profile and the propagation constants are computed from the resonance peaks of the excitation efficiency versus propagation constant characteristics. It has been shown that the channel wavelength tuning can be achieved by varying the Y-branching angle at the input and output of the device or by a slight variation of two-mode-section length. The method of electro-optic fine tuning of the channel wavelength and channel separation of the device has also been investigated. A cascaded structure with proper parameters for four-channel application is also simulated and the results are presented. 相似文献
109.
Wang Chang-biao Tu Jian-nan Jian Hua-bei Sun Yan 《International Journal of Infrared and Millimeter Waves》1986,7(7):1005-1035
The kinetic theory based on the expansion of local field in the guiding center coordinate system, presented by paper[1]–[3], has successfully developed into a theoretical system. The mathematical background and physical explanation of setting up the guiding center coordinate system is expounded in the paper. By using the methods of the guiding center and waveguide coordinate systems respectively, the same dispersion equations for interaction of an axially symmetrical single momentum electron beam with TEmn field in the circular waveguide are rigorously derived. A number of mistakes in paper[4] are indicated as well. 相似文献
110.
Hiroki Hotta Kazuya Tatsuno Yoji Hattori Takuya Hashimoto Masayuki Uehara Kin-ichi Tsunoda 《Electrochemistry communications》2008,10(9):1351-1354
The H+ concentration change was monitored near an electrode surface through an electrolysis using a slab optical waveguide technique. Indium tin oxide transparent electrode modified by porous insulating polymer to which methyl red was covalently immobilized was used as a guiding layer, and the absorbance change of the polymer film was monitored. H+ generation at the vicinity of the electrode through the oxidation of ascorbic acid could be monitored by this technique. 相似文献