Plasmon resonance differences between the near- and far-field and implications for molecular detection

Benjamin M. Ross, Savas Tasoglu, Luke P. Lee

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review

10 Scopus citations


The localized surface plasmon resonance (LSPR) of a nanoplasmonic particle is often considered to occur at a single resonant wavelength. However, the physical measures of plasmon resonance, namely the far-field measures of scattering, absorption, and extinction, and the near-field measures of surface-average or maximum electric field intensity, depend differently on the particle polarizability, and hence may be maximized at different wavelengths. We show using analytic Mie theory that the differences in peak wavelength between the near- and far-fields can reach over 200 nm for nanoparticle sizes commonly used in spectroscopy applications. Using finite element analysis, we also consider the effect of varying particle shape to spheroidal geometries, and consider polarization dependence. Using the quasi-static and extended quasi-static approximation, we show that the differences between the near- and far- field measures of plasmon resonance can be largely explained by radiation damping effects. We suggest that accounting for these differences is relevant both for optimizing device design, and for improving fundamental understanding of surface-enhanced mechanisms such as surface-enhanced Raman spectroscopy (SERS).

Original languageEnglish
Title of host publicationPlasmonics
Subtitle of host publicationMetallic Nanostructures and Their Optical Properties VII
StatePublished - 2009
EventPlasmonics: Metallic Nanostructures and Their Optical Properties VII - San Diego, CA, United States
Duration: 2 Aug 20096 Aug 2009

Publication series

NameProceedings of SPIE - The International Society for Optical Engineering
ISSN (Print)0277-786X


ConferencePlasmonics: Metallic Nanostructures and Their Optical Properties VII
Country/TerritoryUnited States
CitySan Diego, CA


  • Biomolecular detection
  • Far-field
  • Finite element method
  • Localized surface plasmon resonance (LSPR)
  • Mie theory
  • Near-field
  • Plasmonics
  • Quasi-static approximation
  • Surface-enhanced Raman spectroscopy (SERS)


Dive into the research topics of 'Plasmon resonance differences between the near- and far-field and implications for molecular detection'. Together they form a unique fingerprint.

Cite this