Dependence between the Refractive-Index Sensitivity of Metallic Nanoparticles and the Spectral Position of Their Localized Surface Plasmon Band: A Numerical and Analytical Study

作者:Saison Francioso Ophelie; Leveque Gaetan; Boukherroub Rabah; Szunerits Sabine; Akjouj Abdellatif*
来源:Journal of Physical Chemistry C, 2015, 119(51): 28551-28559.
DOI:10.1021/acs.jpcc.5b08357

摘要

The refractive-index sensitivity of metallic nanoparticles was investigated numerically using the FDTD method as well as analytically. The obtained results show that the sensitivity of nanoparticles situated in a homogeneous host matrix is independent of their shape. Moreover, it exclusively depends on the LSPR band location, the dielectric function of the metal constituting the nanoparticles, and the refractive index of the host matrix. In the case of nanoparticles deposited on a substrate or in close interaction with it, the sensitivity is however dependent on the shape. Additionally, a loss of sensitivity is observed. Different theoretical trails are examined in order to better understand those phenomena. The study emphasizes that the shape-dependent sensitivity can be related to the modification of the depolarization factors of the nanoparticles in the presence of a substrate.

  • 出版日期2015-12-24