Plasmonic high-quality factor resonators with narrow surface plasmon resonance (SPR) linewidths are extremely significant for surface-enhanced Raman scattering, optical sensors, imaging, and color filters. Unfortunately, extensive research on narrowing SPR linewidths is mainly based on noble metal nanostructures that are restricted by intrinsic loss. Here, heterostructures consisting of metal and dielectric metaphotonics are experimentally designed and fabricated for elaborating SPR linewidths. The results demonstrate that the SPR linewidths can be narrowed by 66.7% relative to that of aluminum nanostructures. The resonant linewidths are directly shrunk due to the interaction between low loss in the semiconductor nanostructures and electromagnetic confinement in the metal counterparts. Meanwhile, the resonant wavelength governed by heterostructure configurations shifts from 600 to 930 nm. This work will pave an avenue toward controlling resonant linewidths of metal-dielectric heterostructures for numerous applications.

中文翻译：

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金属介电异质结构中极窄的谐振线宽

具有窄表面等离子共振 (SPR) 线宽的等离子高品质因数共振器对于表面增强拉曼散射、光学传感器、成像和滤色片具有极其重要的意义。不幸的是，关于缩小 SPR 线宽的广泛研究主要基于受固有损耗限制的贵金属纳米结构。在这里，通过实验设计和制造由金属和介电超光子学组成的异质结构，用于详细说明 SPR 线宽。结果表明，相对于铝纳米结构，SPR 线宽可以缩小 66.7%。由于半导体纳米结构中的低损耗和金属对应物中的电磁限制之间的相互作用，谐振线宽直接缩小。同时，由异质结构配置控制的谐振波长从 600 nm 变为 930 nm。这项工作将为控制多种应用的金属介电异质结构的谐振线宽铺平道路。