Abstract. We study the near-infrared properties of spherical multishell nanoparticles comprising a loss-less dielectric core enclosed by a concentric layering of metallic–dielectric–metallic nanoshells. The coupling between the metallic shells induces plasmon resonance redshifts and peak splitting in the absorption spectra of the layered particle relative those of the metallic constituents. We use full-wave electromagnetic analysis to investigate changes in the absorption spectra as a function of key parameters including the material properties of the inner and outer metallic shells and the aspect ratio of their inner and outer radii. We systematically vary the aspect ratios and quantify the degree of plasmonic coupling between the metallic nanoshells. Our analysis reveals conditions under which the spectral resonance peaks blueshift and/or redshift. We consider bimetallic particles with gold and silver nanoshells and determine the dependency of plasmon resonance peak shifting and splitting as a function of the order of these material layers, i.e., as inner or outer shells.

中文翻译：

---

多壳双金属纳米粒子中等离子体模式的杂化：数值研究

摘要。我们研究了球形多壳纳米粒子的近红外特性，该纳米粒子包含一个由金属-电介质-金属纳米壳同心分层包围的无损电介质核。金属壳之间的耦合导致层状粒子相对于金属成分的吸收光谱中的等离子体共振红移和峰分裂。我们使用全波电磁分析来研究作为关键参数的函数的吸收光谱的变化，包括内部和外部金属壳的材料特性以及它们的内外半径的纵横比。我们系统地改变纵横比并量化金属纳米壳之间的等离子体耦合程度。我们的分析揭示了光谱共振峰蓝移和/或红移的条件。我们考虑具有金和银纳米壳的双金属颗粒，并确定等离子体共振峰位移和分裂的依赖性作为这些材料层顺序的函数，即作为内壳或外壳。