Second harmonic excitation spectroscopy of silver nanoparticle arrays

Andrew M. Moran, Jiha Sung, Erin M. Hicks, Richard P Van Duyne, Kenneth G. Spears*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

53 Scopus citations

Abstract

Frequency-scanned excitation profiles of coherent second harmonic generation (SHG) were measured for silver nanoparticle arrays prepared by nanosphere lithography. The frequency of the fundamental beam did not coincide with the localized surface plasmon resonance (LSPR) of the nanoparticles and was tuned so that the coherent second harmonic (SH) emission was in the region of the LSPR at 720-750 nm. The SH emission from the arrays was compared with a smooth silver film to identify an enhancement of SH emission efficiency that peaks near ∼650 nm for nanoparticles 50 nm in height. The polarization and orientation dependence of this enhancement suggests that it is related to a dipolar LSPR mode polarized normal to the plane of the substrate. Linear extinction spectra are dominated by in-plane dipoles and do not show this weak out-of-plane LSPR mode. The nanoparticle arrays are truncated tetrahedrons symmetrically oriented by nanosphere lithography to cancel SH from in-plane dipoles which allows observation of the weak out-of-plane component.

Original languageEnglish (US)
Pages (from-to)4501-4506
Number of pages6
JournalJournal of Physical Chemistry B
Volume109
Issue number10
DOIs
StatePublished - Mar 17 2005

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry
  • Surfaces, Coatings and Films
  • Materials Chemistry

Fingerprint

Dive into the research topics of 'Second harmonic excitation spectroscopy of silver nanoparticle arrays'. Together they form a unique fingerprint.

Cite this