Plasmonic plano-semi-cylindrical nanocavities with high-efficiency local-field confinement

Abstract

Plasmonic nanocavity arrays were achieved by producing isolated silver semi-cylindrical nanoshells periodically on a continuous planar gold film. Hybridization between localized surface plasmon resonance (LSPR) in the Ag semi-cylindrical nanoshells (SCNS) and surface plasmon polaritons (SPP) in the gold film was observed as split bonding and anti-bonding resonance modes located at different spectral positions. This led to strong local field enhancement and confinement in the plano-concave nanocavites. Narrow-band optical extinction with an amplitude as high as 1.5 OD, corresponding to 97% reduction in the transmission, was achieved in the visible spectrum. The resonance spectra of this hybrid device can be extended from the visible to the near infrared by adjusting the structural parameters.

Geometric frustration in a hexagonal lattice of plasmonic nanoelements

“…Plasmonic nanoelement arrays have been widely used for a variety of applications including enhanced spectroscopies [1][2][3][4][5], perfect absorbers [6][7][8], plasmonic lasing [9][10][11] or energy harvesting [12]. Innumerable research has been done in fully characterizing the spectral response or the field enhancement (FE) of a variety of nanoantennas [2,4,[13][14][15][16].…”

Creation of Plasmon-Based Nanoantenna for Hydrogen Production

“…The resonant photon wavelengths vary for different metals [1], where the most commonly used materials are precious metals such as gold, silver and aluminium [3]. In a metal-insulator-metal (MIM) nanoantenna system [4], the interaction between light and a plasmon-active metal [5] generates surface-plasmon polaritons (SPPs) [2,[4][5][6][7] at the plasmon-active metal and dielectric interface [2]. SPPs are typically observed in structures such as gratings [2,8,9] and nanowires [5].…”

“…Typically, the nanostructures used for HER are metal-semiconductor composites [1][2][3]13,15] or complex MIM structures [4,12,14]. In this work, we propose a simple MIM nanoantenna design made from gold as the plasmon-active metal, polystyrene (PS) as the insulator and platinum as the HER catalyst.…”

Conductive connection induced speed-up of localized-surface-plasmon dynamics

“…The dielectric constant of the environmental medium is another essential factor that influences the spectroscopic response of the plasmonic nanostructures [6][7][8], which is the basis for the plasmonic sensors and ultrafast optical switching devices. Hybridization between LSPR and surface plasmon polaritons (SPP) is an effective approach to enhance the functions or extend the potential applications of the devices [9][10][11]. Such hybrid plasmons can be achieved by combining continuous metallic films with isolated nanostructures.…”

“…Physics involved in the interaction between the metallic nanoparticles and thin films have been studied experimentally in a progressively elongated silver nanoparticle and a silver film [12] and theoretically in the system consisting of a gold nanoparticle (AuNP) and a gold film with adjustable separation distance [13]. In particular, the electron-electron and electron-phonon interactions in LSPR [14,15] and in the hybrid systems [10,11] can be utitlized to achieve ultrafast optical switching devices. In this work, we investigate how a continuous gold film (AuFilm) deposited on the top surface of the isolated AuNPs influences the steady-state and ultrafastspectroscopic response of LSPR of such conductively connected AuNPs (CCAuNPs) sitting on a glass substrate.…”