We theoretically investigate the influence of the shape of nanoholes on plasmonic behaviours in coupled elliptical metallic nanotube arrays by the finite-difference time-domain (FDTD) method. We study the structure ...We theoretically investigate the influence of the shape of nanoholes on plasmonic behaviours in coupled elliptical metallic nanotube arrays by the finite-difference time-domain (FDTD) method. We study the structure in two cases: one for the array aligned along the minor axis and the other for the array aligned along the major axis. It is found that the optical properties and plasmonic effects can be tuned by the effective surface charges as a result of the variation in the minor axis length. Based on the localized nature of electric field distributions, we also clearly show that the presence of localized plasmon resonant modes originates from multipolar plasmon polaritons and a large magnitude of opposing surface charges build up in the gap between adjacent nanotubes.展开更多
基金Project supported by the Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20100162110068)the Graduate Education Innovation Project of Central South University (Grant No. 2010ssxt010)the Hunan Provincial Innovation Foundation for Postgraduate (Grant No. CX2009B029)
文摘We theoretically investigate the influence of the shape of nanoholes on plasmonic behaviours in coupled elliptical metallic nanotube arrays by the finite-difference time-domain (FDTD) method. We study the structure in two cases: one for the array aligned along the minor axis and the other for the array aligned along the major axis. It is found that the optical properties and plasmonic effects can be tuned by the effective surface charges as a result of the variation in the minor axis length. Based on the localized nature of electric field distributions, we also clearly show that the presence of localized plasmon resonant modes originates from multipolar plasmon polaritons and a large magnitude of opposing surface charges build up in the gap between adjacent nanotubes.