Plasmonic properties of individual heterogeneous dimers of Au and In nanospheres

• DOI: 10.1016/j.physleta.2020.127131
• Publication Date: 2021-01-08T10:18:13Z
• Authors: RuXin Zhang; Lu Sun; ChaoLing Du; TianYi Fu; YangXi Chen; WangXu Rong; Xiang Li; DaNing Shi
• Keywords: Visible spectrum

Abstract In this paper, a new type of heterogeneous dimer of Au and In nanospheres is proposed, which refractive index (RI) sensing and surface enhanced Raman scattering (SERS) performances are numerically predicted by finite element method. It combines both LSPR advantages of Au and In. Under visible and UV light excitations, the maximum RI sensitivity factor S is revealed to reach 259 nm/RIU and 535 nm/RIU, while the maximum SERS enhancement factor reaches ∼107 and 105, respectively. They are improved significantly than that of monomer counterparts. The near-electric-field coupling effect on the dimer localized surface plasmon resonance (LSPR) peak wavelength, S, and the corresponding fractional shifts are discussed, which provide alternatives to estimate the gap distance in-between dimer components. It holds great promise for future designing Au, In heterogeneous nanostructure based SERS and RI sensing substrates which work efficiently both at visible and UV light regions.