Strong plasmon coupling in self-assembled superparamagnetic nanoshell chains

Abstract

Construction of ordered patterns of plasmonic nanoparticles is greatly important for nanophotonics relevant applications. We have reported a facile and low-cost magnetic field induced self-assembly approach to construct plasmonic superparamagnetic nanoshell (SN) chains up to several hundred micrometers in a few seconds in a large area without templates or other assistance processes. Experimental and theoretical investigations of the near- and far-field optical properties indicate that the super- and sub-radiant modes of the SN chains continuously redshift with the increase of SN number and the Fano resonance emerges in the infinite double- and triple-line SN chains. Strong plasmon coupling effects in the SN chains result in great electric field enhancements at visible and infrared wavelengths, which indicates that these chain structures potentially can be used as a common substrate for both surface enhanced Raman scattering (SERS) and surface-enhanced infrared absorption (SEIRA) application. This fabrication method also offers a general strategy alternative to top-down processing that enables the construction of nanostructures for metamaterials, electromagnetic energy transport, and optical waveguide.

Multicomponent Plasmonic Nanoparticles: From Heterostructured Nanoparticles to Colloidal Composite Nanostructures

“…To fabricate one-dimensional (1D) plasmonic nanochains assembled with the noble metal NPs, various NP assembly strategies have been developed. Most of the reported assembly methods require the use of templates, polymers, ligands, or molecular linkers. ,,− ,− For practical applications, the packing density and the pairwise spacing between adjacent NPs within the chain needs to be precisely defined; however, it is difficult to control, align, and fix freely moving NPs in a specific direction and shape. ,− The assembly of the long, geometry-controlled and discrete NPs chains, especially the heterogeneous NPs chains containing more than one component, still remains the pressing challenge. Here, we classify the heterogeneous plasmonic NPs chains into two categories: heterochains composed of different plasmonic monomers and nanochains assembled with heterogeneous plasmonic NPs.…”

Self‐Assembled Silver–Germanium Nanolayer Metamaterial with the Enhanced Nonlinear Response

“…The former uses traditional micro‐ and nanofabrication methods to form materials from composites of desired shapes and order . In the latter, structuring is achieved by a self‐organization process which is controlled by various strategies . One of such self‐organization processes, called segregation, leads to separation of admixture atoms in small regions within the matrix medium, defined by the presence of inhomogeneities in the matrix, such as free surfaces, grain boundaries, interfaces between different phases, or dislocations .…”

Infrared metamaterial for surface-enhanced infrared absorption spectroscopy: pushing the frontier of ultrasensitive on-chip sensing

“…The material choice of the plasmonic device has a strong influence on the SEIRA performance. [112][113][114][115][116][117][118][119][120][121][122][123][124][125] Specifically, the absorption cross-sections depend on the material properties, and the scattering cross-sections of the antenna geometry. [33,126] Therefore, it is necessary to choose proper plasmonic and dielectric material for the performance optimization of SEIRA.…”