Tunable hybridization in metal nanoshell chains

Abstract

We have studied the coupled surface plasmon (SP) modes in periodic metal nanoshellchains by including long range electromagnetic interactions. The eigen-decompositionmethod is used to analyze the dispersion and dissipation of the SP modes. The resultingband structure can be understood as a hybridization between a hole band and a particleband with a structurally tunable band gap in the middle of the first Brillouin zone. Themode quality, which is defined as the imaginary part of the generalized polarizability,increases as the shell thickness decreases. This indicates a larger energy loss and anincreasing coupling between the bands. Through the manipulation of the band structures,the propagation of the coupled SP modes in the nanoshell chain can be controlled.