Adjustable plasmonic resonances of a gold nanotube array with a non-coaxial core

Abstract

The plasmonic resonant properties of a gold nanotube array with a non-coaxial core were investigated using the finite-difference time-domain (FDTD) method. There exist two large photonic band gaps in the transmission spectra for large core offset. It is observed that the plasmonic behaviors can also be tuned by the inter-tube spacing, the size and the thickness of the nanotube with a non-coaxial core in the metallic array structure. Based on the field distribution, we deduce that the lower energy peaks of the spectra are characterized by dipole resonances, while the higher energy peaks are characterized by multipolar resonances.

Keywords:

• plasmonic resonance
• non-coaxial nanotube array
• field distribution
• transmission

Acknowledgements

This work was funded by the Research Fund for the Doctoral Program of Higher Education of China under Grant No. 20100162110068, the Excellent Doctorate Dissertation Foundation of Central South University under Grant No. 2008yb039, and the Postgraduate Innovative Project of Hunan Province under Grant No. CX2009B029.