Effect of Asymmetry on Plasmon Hybridization and Sensing Capacities of Hole-Disk Arrays
Mohammadi R, Ochs M, Andrieu-Brunsen A, Vogel N (2020)
Publication Type: Journal article
Publication year: 2020
Journal
Book Volume: 124
Pages Range: 2609-2618
Journal Issue: 4
Abstract
Plasmonic complementary structures are interesting model systems that combine propagating and localized surface plasmon resonances and allow the fundamental study of their hybridization. In the simplest form, such structures are formed by stacking arrays of nanodisks and nanoholes with matching dimensions. Here, we produce such hole-disk arrays in an experimentally easy and parallel colloidal lithography process with accurate control over vertical alignment and separation between the individual disks and holes. Importantly, our process readily enables symmetry breaking and the design of asymmetric hole-disk arrays with controlled lateral offset between each hole-disk pair. We investigate the coupling between the parental resonances of the two elements as a function of feature size and separation distance and provide a plasmon hybridization scheme to rationalize the resonances. We find that for the asymmetric hole-disk structure, a new, hybrid resonance arises as a peak in the transmission spectra, which is not found in their symmetric analogues. We demonstrate that this new resonance imparts a higher sensitivity in refractive index sensing as it features a pronounced near-field enhancement in between holes and disks. The near-field structure, paired with the accessibility of this separation region in the presented hole-disk structures, implies that this architecture should be sensitive to local changes in the refractive index at the surface of the dielectric layer separating the plasmonic elements. We demonstrate this sensitivity of the asymmetric hole-disk arrays by the detection of the binding of a silane monolayer at the walls of the dielectric silica spacer layer.
Authors with CRIS profile
Reza Mohammadi Eslami
Lehrstuhl für Feststoff- und Grenzflächenverfahrenstechnik
Nicolas Vogel
Professur für Partikelsynthese
Involved external institutions
Germany (DE)How to cite
APA:
Mohammadi, R., Ochs, M., Andrieu-Brunsen, A., & Vogel, N. (2020). Effect of Asymmetry on Plasmon Hybridization and Sensing Capacities of Hole-Disk Arrays. Journal of Physical Chemistry C, 124(4), 2609-2618. https://dx.doi.org/10.1021/acs.jpcc.9b10229
MLA:
Mohammadi, Reza, et al. "Effect of Asymmetry on Plasmon Hybridization and Sensing Capacities of Hole-Disk Arrays." Journal of Physical Chemistry C 124.4 (2020): 2609-2618.
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