设计了一种基于纳米线/间隔层/金属层的纳米激光器结构.该结构中,金属界面的表面等离子体模式与高增益介质纳米线波导模式耦合,提高了场增强效应.采用有限元法,分析了该结构的模式特性和增益阈值随几何尺寸的变化规律.结果表明:该结构具有较低的传播损耗和较强的光场限制能力,有效传播损耗最小值仅为0.013 3,归一化模式面积最小值仅为0.007.该纳米激光器结构可为发展新一代高效纳米激光器件提供理论和技术支持.

A surface plasmonic nano-laser structure based on a nanowire/gap/metal layer was proposed. The models produce a significant field enhancement effect through the mode-coupling between nanowire and metal layer. Modal properties and lasing threshold under different geometric shapes and parameters were investigated and analyzed by the finite element method. Simulation results reveal that this kind of nano-laser has a low propagation loss and high field confinement ability, its minimum propagation loss is only 0.013 3 and the minimum normalized mode area is only 0.007. The results provide theory and technique support to the field of new nano-laser design.