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Title: Plasmon Hybridizations in Compound Nanorod–Nanohole Arrays
This study shows that a hybridized plasmonic mode, represented by an additional transmission peak, in a compound structure consisting of a nanorod embedded in a nanohole can be effectively described as a quasi-dipole oscillator. When two nanorods are introduced into a nanohole, these two quasi-dipoles can couple and hybridize, giving rise to two additional transmission peaks in the enhanced optical transmission spectrum. The relative intensities of these peaks can be con-trolled by adjusting the incident polarization, while their separations can be tuned by modifying the length of the nanorods. The concept of quasi-dipoles in compound nanohole structures can be further extended to predict the coupling behavior of even more complex compound configura-tions, such as multiple nanorods within nanoholes, resulting in the generation of multiple hy-bridization states. Consequently, the shape and response of the transmission peaks can be pre-cisely engineered. This strategy could be used to design nanohole-based metasurfaces for applica-tions such as ultra-thin optical filters, waveplates, polarizers, etc.  more » « less
Award ID(s):
1808271
PAR ID:
10434045
Author(s) / Creator(s):
Date Published:
Journal Name:
Nanomaterials
ISSN:
2079-4991
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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