Impurity-Induced Plasmon Damping in Individual Cobalt-Doped Hollow Au Nanoshells

Abstract

The optical properties of plasmonic nanoparticles in the size range corresponding to the electrostatic, or dipole, limit have the potential to reveal effects otherwise masked by phase retardation. Here we examine the optical properties of individual, sub-50 nm hollow Au nanoshells (Co-HGNS), where Co is the initial sacrificial core nanoparticle, using single particle total internal reflection scattering (TIRS) spectroscopy. The residual Co present in the metallic shell induces a substantial broadening of the homogeneous plasmon resonance line width of the Co-HGNS, where the full width at half-maximum (fwhm) broadens proportionately with increasing Co content. This doping-induced line broadening provides a strategy for controlling plasmon line width independent of nanoparticle size, and has the potential to substantially modify the relative decay channels for localized nanoparticle surface plasmons.3

Dispersive Plasmon Damping in Single Gold Nanorods by Platinum Adsorbates

“…By contrast, the plasmon damping by adsorption or deposition of metal adsorbates with the negative imaginary part of the dielectric function can be a key factor to be considered in the design and fabrication of plasmonic heterostructures as functional nanomaterials. An example was recently given on the effect of Co impurities on the plasmon linewidth of gold nanoshells . For elongated metal nanoparticles, however, little complete information of plasmon damping induced by metal adsorbates is available.…”

Polarized evanescent waves reveal trochoidal dichroism

“…S11). The increase in noise is due to the reduced sensitivity of oblique incidence scattering spectra (35). (E) Summary of symmetry operations relating each geometric isomer to another and the effect on trochoidal and linear dichroism (TD and LD).…”

Hyperthermia using nanoparticles – Promises and pitfalls

“…One concern raised with these shells is that of in vivo instability of the hollow structure and that the residual silver or cobalt in the hollow cavity could result in standalone cytotoxicity since it does not stay contained within the HGNS (50). One potential advantage of residual cobalt present in the metallic shell is that it broadens the plasmon resonance peak of cobalt-HGNSs, allowing tuning of the plasmon peak without changing nanoparticle diameter (51). …”