Extraordinary Light-Induced Local Angular Momentum near Metallic Nanoparticles.

Published

Journal Article

The intense local field induced near metallic nanostructures provides strong enhancements for surface-enhanced spectroscopies, a major focus of plasmonics research over the past decade. Here we consider that plasmonic nanoparticles can also induce remarkably large electromagnetic field gradients near their surfaces. Sizeable field gradients can excite dipole-forbidden transitions in nearby atoms or molecules and provide unique spectroscopic fingerprinting for chemical and bimolecular sensing. Specifically, we investigate how the local field gradients near metallic nanostructures depend on geometry, polarization, and wavelength. We introduce the concept of the local angular momentum (LAM) vector as a useful figure of merit for the design of nanostructures that provide large field gradients. This quantity, based on integrated fields rather than field gradients, is particularly well-suited for optimization using numerical grid-based full wave electromagnetic simulations. The LAM vector has a more compact structure than the gradient matrix and can be straightforwardly associated with the angular momentum of the electromagnetic field incident on the plasmonic structures.

Full Text

Duke Authors

Cited Authors

  • Alabastri, A; Yang, X; Manjavacas, A; Everitt, HO; Nordlander, P

Published Date

  • April 12, 2016

Published In

Volume / Issue

  • 10 / 4

Start / End Page

  • 4835 - 4846

PubMed ID

  • 27045994

Pubmed Central ID

  • 27045994

Electronic International Standard Serial Number (EISSN)

  • 1936-086X

International Standard Serial Number (ISSN)

  • 1936-0851

Digital Object Identifier (DOI)

  • 10.1021/acsnano.6b01851

Language

  • eng