Overlayers on silver nanotriangles: Field confinement and spectral position of localized surface plasmon resonances.
We studied the spectral evolution of plasmon modes associated with silver nanotriangles as a function of dielectric overlayer thickness in the range of 5-300 nm. A substantial red-shift of the resonance is observed that oscillates with increasing over-layer thickness. We explain this previously unreported oscillation through the cavity quantum electrodynamical effect of the array of triangles combined with the dielectric overlayer. The red-shift, though substantial, is less than expected. Comparison with numerical models indicates that this discrepancy is due to very tight field confinement around the tips of the triangles.
Murray
W Andrew
WA
School of Physics, University of Exeter, Exeter, EX4 4QL, UK. w.a.murray@ex.ac.uk
Suckling
James R
JR
Barnes
William L
WL
D003198:Computer Simulation; D008027:Light; D008956:Models, Chemical; D008958:Models, Molecular; D049329:Nanostructures / Q000032:analysis / Q000737:chemistry*; D010316:Particle Size; D011789:Quantum Theory; D012834:Silver / Q000032:analysis / Q000737:chemistry*; D013113:Spin Labels; D020349:Surface Plasmon Resonance / Q000379:methods*
D013113:Spin Labels; D012834:Silver