稀土纳米晶/金属纳米粒子共掺杂的微纳光纤激光器

Nanofiber lasers have attracted great attention owing to their potential applications in photonic integrated circuits, quantum electrodynamics, biosensors, etc. In view of problem that laser gain medium coefficient and micro cavity mode selection ability, the proposed co-doped rare earth nanocrystals and metal nanoparticles in nanofiber, through the control of metal nanostructures, resulting in different resonance position plasma near field enhancement effect of rare earth ions at a particular wavelength luminescence intensity enhancement. In order to improve the mode selection ability of micro cavity laser, we have developed a self coupled micro cavity assembly based on composite doped polymer nanofibers. The project studied the energy transfer principle and luminescence enhancement mechanism of metal nanoparticles and rare earth nanocrystals; the metal nanoparticle diameter, morphology, concentration and other parameters influence on the luminescence of rare earth ions. Using micromanipulation of single nanofiber assembly into the cavity; according to the comparison between theoretical simulation and experimental results for cavity structure optimization, reveal the mode selection mechanism of microcavity, provide a foundation theoretical and technical support for the realization of single longitudinal mode, tunable nanolaser device.

微纳光纤激光器在光子集成芯片、量子电动力学、生物传感等领域有重要的应用前景。针对目前微纳米激光器的增益介质发光效率低，微腔的模式选择能力差问题，本项目提出了稀土纳米晶和金属纳米粒子共掺杂在微纳光纤内部，通过控制金属纳米结构，产生不同共振位置等离子体近场增强效应，实现稀土离子在特定波长处发光效率的增强；研制基于复合材料掺杂聚合物微纳光纤组装成自耦合微腔，解决微腔激光器模式选择能力问题。项目研究金属纳米粒子与稀土纳米晶之间能量传递原理和发光增强机制；金属纳米粒子直径、形貌、浓度等参量对稀土离子发光增强的影响规律；并利用显微操作单根微纳光纤组装成腔；通过理论仿真与实验结果对比进行腔体结构优化，揭示微腔模式选择机制，为实现单纵模、可调谐的微纳光纤激光器件奠定理论和技术基础。

稀土元素掺杂光纤的上转换发光具有巨大的应用前景，它结合了上转换发光和光波导的优势。特别是微米量级的光纤，由于光纤光学技术在微观层面的研究，以及这些材料在生物化学传感、生物医学和纳米光子学等领域的灵活应用，受到了广泛的关注。本项目主要研究稀土元素Er3+/Yb3+和Tm3+/Yb3+共掺杂的微结构光波导，通过将稀土元素分散在聚合物基质中来实现稀土元素的上转换发光，并研究其光学特性。通过研究光纤的传输损耗和耦合效率，掺杂稀土元素的聚合物光纤具有低损耗系数和高耦合效率。研究了基于稀土元素掺杂聚合物光纤的温度传感特性。通过改变环境温度，得到上转换发光强度与温度的关系，并计算得到温度灵敏度。基于掺Er的微结构光纤在299-343K区间表现出更高的温度灵敏度，且实现了沿着微结构光纤的方向上空间分辨率为10 um的分布式温度测量，其误差小于2K。随着稀土掺杂聚合物在上转换激光器、光纤放大器等领域的广泛研究，具有更高灵敏度和更小误差的微结构的分布式温度测量将会应用在生物光学以及微电子学领域。