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Diffractive dipolar coupling in non-Bravais plasmonic lattices
David Becerril1, Omar Vázquez1, Diego Piccotti2
1Instituto de Física, Universidad Nacional Autónoma de México Apartado Postal 20-364 México D.F. 01000 Mexico pirruccio@fisica.unam.mx.
Nanoscale Advances
|September 22, 2022
Summary
Researchers studied honeycomb plasmonic lattices made of silver nanospheres. They found asymmetric near-field distributions due to interactions between sublattices, revealing insights into non-Bravais lattice physics.
Area of Science:
- Plasmonics
- Nanophotonics
- Condensed Matter Physics
Background:
- Honeycomb lattices are non-Bravais lattices with unique properties.
- Surface lattice resonances (SLRs) are collective oscillations of plasmons in ordered nanoparticles.
Purpose of the Study:
- To experimentally investigate SLRs in free-standing honeycomb plasmonic lattices.
- To analyze the dispersion relation and near-field properties of these SLRs.
- To understand the role of sublattice interactions in non-Bravais lattices.
Main Methods:
- Experimental fabrication of honeycomb lattices from silver nanospheres.
- Measurement of surface lattice resonances.
- Numerical simulations (e.g., Finite-Difference Time-Domain).
- Analytical modeling of dipole-dipole interactions.
Main Results:
- Observed and analyzed SLRs in honeycomb plasmonic lattices.
- Demonstrated asymmetric near-field distributions attributed to dipole-only interactions between triangular sublattices.
- Investigated the impact of varying interparticle distances on lattice symmetry and diffraction.
Conclusions:
- Honeycomb plasmonic lattices exhibit distinct plasmonic behaviors governed by sublattice interactions.
- The findings provide a framework for understanding and designing non-Bravais plasmonic systems.
- Results highlight the transition between Bravais and non-Bravais lattice characteristics.
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