【作者】 刘丽飒；

【导师】 吴伯僖； 蔡志平；

【作者基本信息】 厦门大学 ， 凝聚态物理， 2005， 博士

【摘要】 本论文研究利用CO₂激光作为热源加工制备熔锥光纤耦合型光学球微谐振腔器件。搭建球微腔及其耦合用熔锥光纤的一体化制备装置,完成了微米量级的球微腔的制备。理论上,讨论了熔锥光纤耦合型光学球微谐振腔器件对于熔锥锥腰直径和球微腔直径的要求。对熔锥光纤和微球之间的耦合性质进行研究。文章首先对近年来球微腔特性的研究状况和球微腔耦合器的近期发展作了简要回顾。从通信波段应用的角度出发,选择了现今比较成熟的熔锥光纤耦合型球微腔光器件作为研究对象。在对几种球微腔和熔锥光纤的制备方法进行比较后,选择了CO₂激光作为热源进行加工制备。通过对球微腔的光场特性和熔锥光纤的传输特性各自独立的分析,给出球腔直径和熔锥光纤锥腰直径的选择依据。采取弱导近似的方法对不同半径的锥腰中归一化径向相位常数U和传播常数较精确数值计算,给出了熔锥光纤锥腰作为球腔激光输入输出耦合器件,对于不同直径球腔匹配时的锥腰直径。利用H. J. Shaw提出的单模光纤定向耦合器的分析方法,结合微球谐振腔的特点,对熔锥光纤与球微腔耦合系统进行近似的理论分析。采取这种近似方法对熔锥光纤与球微腔耦合系统处于强耦合、弱耦合和临界耦合的理论模拟和分析与业已报道实验的结果基本一致。在结构和控制方法上对国外CO₂激光熔拉锥系统进行了改进,简化了实验装置。选用了焦距更短的聚焦透镜。对光纤熔拉加工过程中热平衡时光功率条件进行了计算,利用理论计算的结果简化了装置的控制方法。收到了良好的实验效果。最后将CO₂激光熔拉锥系统进行扩展,使其同时具备加工在空气中热更多还原

【Abstract】 In this paper, we had studied the CO₂ laser fabrication of microsphere resonators coupled by biconical tapered fibers. The integrated fabrication system of melt-drawn biconical tapered fibers and microsphere resonators using a CO₂ laser as its heat source has been developed. Silica micospheres and glass microspheres doped by Nd+3 had been made using this fabrication system. The sizes of the microsphere and biconical tapered fiber waist had been discussed for optical devices. The characteristic of the coupling between the microsphere resonator and the biconical tapered fiber had been studied.In the first part, we had a general review of the history of microsphere resonance in theory and experiment study. The developments of the coupled microsphere system had been introduced. It had been approved by experiments that the biconical tapered fiber is a good energy exchange device for microspheres. The biconical tapered fiber had been selected as the coupler of the microsphere resonance in our study. Several fabrication methods of the biconical tapered fiber and the microsphere had been compared. The precise fabricating technique of CO₂ laser had been used in our experiments.Secondly, the characters of the microsphere resonance and the biconical tapered fiber had been analyzed separately. The best ranges of the radii of the microsphere resonance and the biconical tapered fiber for optical devices had been given. Using the weakly guided mode, the normalized radial phase constants （U） and the propagation constants for biconical tapered fiber with different waist radii had been calculated precisely. The correspondence relationship for radii had been given when the tapered fiber as pump method to phase-matched excite the WGM laser in the microsphere. By using the H. J. Shaw’s method for studying the single-mode fiber directional couplers and更多还原