设计了一种带有金属脊和氟化镁夹层的紫外混合表面等离子体纳米激光器。在COMSOL Multiphysics软件的基础上, 使用有限元法分析了所设计激光器结构的电场分布、模式特性、品质因数和增益阈值。结果表明: 在工作波长为390 nm的紫外波段, 通过最优参数设计, 其光场约束可达到较好的深亚波长水平, 同时保持高的品质因数、低的损耗和阈值。与平坦金属层结构相比, 在相同的参数下, 所设计的结构具有更强的光场限制能力和更强的微腔束缚能力, 有潜力使纳米设备趋于小型化和集成化。

In this paper, a novel hybrid plasmonic nanolaser with a metal ridge and a MgF2 dielectric layer at ultraviolet band is demonstrated. The electric field distribution, the modal properties, the quality factor and the lasing threshold are investigated by using the finite-element method on the basis of the COMSOL Multiphysics platform. At the 390 nm working wavelength, the structure of the nanolaser can reach good deep-subwavelength mode confinement by optimizing its geometric parameters, while maintaining high quality factor and low propagation loss and low gain threshold. Compared to the previously reported structure with a metal plate, this structure has stronger capacity of field confinement and microcavity bound with the same geometric parameters. The structure shows potential to promote miniaturization and integration of lasers.