Dual resonant bands in UV and the visible range were simultaneously observed in the enhanced optical transmission (EOT) through star-shaped plasmonic structures. EOTs through four types of polygonal bull's eyes with a star aperture surrounded by the concentric star grooves were analyzed and compared for 3, 4, 5, and 6 corners, using finite difference time domain (FDTD) method. In contrast to plasmonic resonances in the visible range, the UV-band resonance intensity was found to scale with the number of corners, which is related with higher order multipole interactions. Spectral positions and relative intensities of the dual resonances were analyzed parametrically to find optimal conditions to maximize EOT in UV-visible dual bands.
Bibliographical noteFunding Information:
This work was supported in part by Institute of Physics and Applied Physics, Yonsei University, in part by ICT R&D Program of MSIP/IITP (2014-044-014-002), in part by Nano Material Technology Development Program through NRF funded by the MSIP (NRF- 2012M3A7B4049800).
All Science Journal Classification (ASJC) codes
- Atomic and Molecular Physics, and Optics