Plasmonic surface lattice resonances (SLRs) supported by metal nanoparticle arrays have a range of appealing characteristics such as extremely narrow linewidths and greatly enhanced near fields, and thus are attractive in diverse applications. Improving the quality factor of SLRs is important for many applications and thus it has been the focus in this field. In this work, we report high quality out-of-plane SLRs supported by two-dimensional metal nanohemisphere arrays embedded in a symmetric dielectric environment. These SLRs, excited under oblique incidence with TM polarization, can have an ultra-narrow resonant linewidth (∼ 0.9 nm) at visible wavelengths around 715 nm. This corresponds to an exceptionally high quality factor of 794, which is ten times that of the widely-adopted nanorods. We attribute this striking performance to the nanohemisphere geometry, which greatly relaxes the stringent requirement on the height of nanoparticles for supporting out-of-plane SLRs, reducin...

中文翻译：

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金纳米半球阵列中异常窄的等离子体表面晶格共振

金属纳米粒子阵列支持的等离子表面晶格共振（SLR）具有一系列吸引人的特性，例如极窄的线宽和极大增强的近场，因此在各种应用中具有吸引力。对于许多应用而言，提高SLR的品质因数很重要，因此一直是该领域的重点。在这项工作中，我们报告了嵌入对称电介质环境中的二维金属纳米半球阵列所支持的高质量平面外单反相机。这些SLR在TM偏振光的倾斜入射下激发，在715 nm附近的可见波长处可以具有超窄谐振线宽（约0.9 nm）。这对应于794的极高的品质因数，这是被广泛采用的纳米棒的十倍。