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101.
Hongsik Jung 《Fiber and Integrated Optics》2016,35(4):161-180
The need for electric-field sensing technology has widely increased, playing a critical role in various scientific and technical areas. This article comprehensively reviews and compares Ti:LiNbO3 integrated optic electric-field sensors, including the asymmetric Mach-Zehnder interferometer (MZI), 1 × 2 directional coupler (DC), and Y-fed balanced-bridge Mach-Zehnder interferometer (YBB-MZI), based on the operating principles, the electrical and optical performance, and measurements of each fabricated device. We also discuss future works to improve the sensitivity, operating stability, response speed, and bandwidth. 相似文献
102.
Abstract This article presents an all-optical multi-mode interference switch in which the non-linear directional coupler is utilized to realize a passive phase shifter. The proposed structure can be used either as a 1 × 2 or a 2 × 2 switch, with two inputs applied simultaneously in the latter case. The operation of the device is mainly based on the phase difference of the inputs of the multi-mode interference section. The beam propagation method is used for the design and simulation of the structure. The simulation results approve the low sensitivity on wavelength and fabrication tolerances. The crosstalk of the structure is equal to ?31.6 dB. 相似文献
103.
A pick-up parallel-setting high order mode coupler(pps-HOM coupler)has been fabricated at Peking University.It has been tested on a coaxial transmission line and a 2-cell TESLA-shape copper cavity.The test result of the 2-cell TESLA cavity shows that the coupler can cut off the fundamental mode TM010 and absorb HOMs electively.As its RF properties are insensitive to the probe dip length,there is no need to adjust the probe repeatedly during practical operation. 相似文献
104.
Abstract An accurate vector finite element solution of the nonsynchronous directional coupler problem is presented, illustrating coupling lengths and supermodes of the complete structures. 相似文献
105.
T. Phattaraworamet T. Saktioto J. Ali M. Fadhali P.P. Yupapin J. Zainal S. Mitatha 《Optik》2010,121(24):2240-2244
We propose a simple kinetic model that can be used to improve the coupling coefficient value of a single mode fiber coupler in the fabrication process. The proposed model is time independent, where the internal and external parametric functions are included. The simulation is integrated over the coupling ratio range for the various fiber separations. The coupling coefficient value of the device is examined by using the coupling ratio range from 1% to 75%. The result obtained is compared with the experimental results, where it is noted that the separation of fiber cores significantly affects the coupling coefficient, exhibiting exponential behavior. We also found that the coupling coefficient gradient is significantly changed with respect to the coupling ratio. This model can be used to determine power losses of the fiber coupler at the coupled region, while the fabrication of the fiber coupler is operated. 相似文献
106.
107.
熔锥型光纤耦合器宽带特性研究 总被引:7,自引:1,他引:6
报道了在常规熔锥型单模光纤定向耦合器工艺基础上,以氢氟酸腐蚀法,将两光纤耦合区直径腐蚀成适当比例,用水平直接熔融拉锥系统,将耦合区域拉制成非对称臂组合波导,从而获得了具有宽频带特性、且尺寸较小的单模光纤定向耦合器,实验结果说明:通过控制耦合区长度,可以使耦合器耦合功率在某个特定波长附近、预定小于100%分束比上具有相当平坦(宽带)特性;从而,通过控制组合波导的不同直径比,可望得到不同分束比宽带耦合 相似文献
108.
Hongliang Ren Chun Jiang Weisheng Hu Mingyi Gao Jingyuan Wang 《Optical and Quantum Electronics》2006,38(8):645-654
In the paper, a novel power-splitting scheme based on two dimensional photonic crystal (2D PhC) is proposed. The structure can be divided into three sections, including the input waveguide, coupling region, and output region, and the latter two sections consist of two parallel waveguides placed in proximity. The operation principle of the splitter is that only one of the super-modes splitting from the directional coupler can propagate through coupling region in the frequency range of interest. The radius of air holes next to the guiding region in coupling region is increased to avoid the acute back reflection at the entrance to the input waveguide induced by the modes mismatch between the input waveguide and coupling region. While in output region, the radius of these corresponding air holes is also increased so that the two splitting super-modes have same propagation constants to avoid the coupling between the two output waveguides. Moreover, as the length of coupling region is varied, its influence on the splitting performance is discussed, and it is verified that the relationship between the splitter length and bandwidth has a trade-off. 相似文献
109.
制备波导光栅的相位掩膜技术 总被引:2,自引:0,他引:2
制备波导光栅的相位掩膜技术*马少杰李燕徐迈林久令(中国科学院长春物理研究所,长春130021)(中国科学院激发态物理开放研究实验室,长春130021)关键词光波导,光栅耦合器,全息光栅自从70年Dakss等人首次报道了集成光波导光栅器件以来[1],波... 相似文献
110.