摘要
To investigate the optical properties of the ternary nanostructures, the nanodisk, core–shell, and three-sphere structures are constructed. The extinction coefficients and electric near-field distributions of these structures are calculated by the discrete dipole approximation(DDA) method. The result shows that the nanodisk structure has the best extinction efficiency in the three structures. Furthermore, several three-material combinations of the nanodisk structures are investigated. The ternary nanodisk structure composed of TiO_(2) and two noble metals(Au, Ag or Pt) has higher extinction coefficient and near-field intensity than the nanodisk consisting of Au, TiO_(2) and a semiconductor(Pb Se, Ge, MoS2, CdSe, CdS or TiO_(2)).Especially, TiO_(2)/Ag/Pt has the best extinction efficiency and the max electric near-field intensity. And the extinction spectra of TiO_(2)/Ag/Pt and TiO_(2)/Ag/Au structures are complementary in the visible range. This work conduces to the further research into ternary nanostructure and provides essential information about its performance in visible range.
作者
唐小龙
程新路
曹华亮
曾华东
Xiao-Long Tang;Xin-Lu Cheng;Hua-Liang Cao;Hua-Dong Zeng(Institute of Atomic and Molecular Physics,Sichuan University,Chengdu 610065,China)
基金
Project supported by the National Natural Science Foundation of China(Grant Nos.11774248 and 11974253)。