有源聚合物-玻璃复合光纤的构筑及其随机激光性质

It is well known that there is an evanescent field of propagating light at the interfacial surface between core and cladding of an optical fiber, from which many functional fibers can be developed on the basis of the interactions between the evanescent field of the guided mode and an overlay material that is located on an etched or polished surface near the core of the fiber. On the other hand, optical properties of polymers can be manipulated by specially designed monomers and corresponding polymers, and this character is vividly described as tailoring in the molecular level. These two characters are often combined together in composite optical fibers, in which the core of the composite fiber is inorganic glass and the cladding is organic polymer. There are many methods to fabricate this kind composite optical fiber, however, there is still a need of new method for the fabrication because the composite optical fiber has poor stability and out-of-control structures. This program proposes a new method for the fabrication, in which the evanescent field is used as light source to initiate “click” polymerization on the surface of the glass optical fiber core through a well-defined precursor solution. Polymer cladding obtained in this way contains chromophores and scatterers in order to produce random laser from this composite optical fiber. Around this aim, detailed research work will include following points: transmission model of the polymer/glass composite optical fibers; design and synthesis of each component of the precursor solution according to the model and light initiated “click” polymerization of the precursor solution; “click” polymerization of the precursor solution initiated by evanescent field on the surface of glass fiber core; relationship between the structure of the polymer cladding and the conditions controlling the “click ” polymerization; transmission properties of the active polymer/glass composite optical fiber; spontaneous emission and random laser of the active polymer/glass composite optical fibers fiber. The above content of this project is proposed in terms of results obtained in the previous research work supported by NSFC and meets the need of fiber devices in the coming information society. Research work proposed in this program will make a breakthrough in construction of the interfacial surface between two phases, composing of organic polymer and inorganic glass, of polymer/glass composite optical fibers by introduction of “click” polymerization under irradiation of evanescent field. Results obtained in the research work will enrich fundamentals for the scientific disciplines concerning interaction between light and polymer, and provide a solid theoretical foundation and abundant technique data for production of active composite optical fibers and random laser fiber devices in the future high-technology industry.

本项目将聚合物的可分子裁剪性质与玻璃光纤的优良波导性质相结合，采用倏逝场引发前驱溶液进行“点击”聚合的方法，在玻璃光纤芯的非平面表面上构筑具有发光性质和光散射性质的聚合物包层，探索这种有源复合光纤各层次结构的形成条件及随机激光性质。主要研究内容包括：能够产生随机激光的复合光纤的传输模型；能够进行“点击”聚合的前驱溶液组成及其各组分的设计、合成及其光引发“点击”聚合；光纤中传输光的倏逝场引发前驱溶液在光纤表面进行的“点击”聚合；光纤表面有源聚合物层的各层次结构与“点击”聚合反应条件之间的关系；有源复合光纤的光传输性质与聚合物包层结构之间的关系；有源复合光纤的自发辐射和随机激光性质。上述各项研究工作的完成，将建立有源聚合物-玻璃光纤的制备方法，获得采用倏逝场引发“点击”聚合反应构筑有源复合光纤各层次结构的基本规律和光激发有源复合光纤产生随机激光的条件，给未来发展有源光纤器件提供有用的基础性数据

本项目将聚合物可以在分子水平进行化学结构裁剪的性质与玻璃光纤的低损耗传输光的性质相结合，提出构筑玻璃光纤为芯，聚合物为包层的复合光纤。同时，面向光纤随机激光，开展有源光纤的随机散射研究。主要研究内容包括，1随机散射的基本问题，如散射的近场散射增强，散射粒子的布朗运动对产生随机激光的影响等；2复合光纤的设计、构筑和性质研究，如复合光纤制作的光镀方法、复合光纤聚合物层的链运动、复合光纤的传感性质和随机激光性质，等。上述研究结果进一步拓展了光子学聚合物研究领域。同时，还给发展光纤传感和光纤激光器奠定了实验基础和提供了参考数据。