Delocalized Lattice Plasmon Resonances Show Dispersive Quality Factors

Abstract

This Letter describes how out-of-plane lattice plasmon (OLP) resonances in 2D Au nanoparticle (NP) arrays show dispersive quality factors. These quality factors can be tailored simply by controlling NP height. Numerical calculations of near-field optical properties and band diagrams were performed to understand the measured dispersion effects of the OLPs. The results revealed that delocalized OLPs are a type of surface Bloch mode composed of many Bloch harmonics. As the OLP dispersion evolves from a stationary state to a propagating state, the nonradiative loss decreases because of weak local field confinement, whereas the radiative loss increases because of strong coupling to the leaky zero-order harmonic.

Mechanotunable Plasmonic Properties of Colloidal Assemblies

“…They suggested that delocalized OLPs are a kind of surface Bloch mode. As the OLP dispersion evolves from a stationary state to a propagating state, the nonradiative loss decreases because of weak local field confinement, whereas the radiative loss increases because of strong coupling to the leaky zero‐order harmonic . In the case of out‐of‐plane excitation, the lattice geometry contributes significantly since stronger coupling occurs in all directions within the plane of the array, as studied by the group of Boyd …”

Surface plasmon enhanced up-conversion from NaYF4:Yb/Er/Gd nano-rods

“…The SPR in metallic periodic structures can be excited when the Bragg condition is satisfied. 21 This type of diffractive coupling has been widely observed in arrays of nanoparticles [22][23][24][25] and nanoholes. [26][27][28] The SPR red shifts as the periodicity of the arrays increases as shown in both the experimental and the simulation results (Figure 2a and Figure 2b, respectively).…”

Lattice plasmon resonance in core-shell SiO_2/Au nanocylinder arrays

“…When the diffraction order changes from evanescent to radiative, a strong dipolar interaction takes place and collective modes could be observed, with the diffraction edge of the 0; 1 superstrate and substrate orders as λ air 0;1 d y and λ sub 0;1 n × d y , respectively. LPMs exhibit several novel characteristics compared with LSPRs, especially the significant suppression of the plasmon radiative damping resulting in narrow resonance lineshape, which could be utilized in bio-sensing [22][23][24], laser action [25][26][27], or SERS [28]. However, most of the LPMs reported were achieved by fabricating Au NPs on the substrate using electron beam lithography.…”