Efficient Raman enhancement and intermittent light emission observed in single gold nanocrystals

Citation
Jt. Krug et al., Efficient Raman enhancement and intermittent light emission observed in single gold nanocrystals, J AM CHEM S, 121(39), 1999, pp. 9208-9214
Citations number
53
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Chemistry & Analysis",Chemistry
Journal title
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
ISSN journal
0002-7863 → ACNP
Volume
121
Issue
39
Year of publication
1999
Pages
9208 - 9214
Database
ISI
SICI code
0002-7863(19991006)121:39<9208:EREAIL>2.0.ZU;2-Z
Abstract
This paper reports two fundamental observations on the size-dependent optic al properties of colloidal gold nanoparticles. First, faceted gold nanocrys tals in the size range of 63 +/- 3 nm have been found to be highly efficien t for surface-enhanced Raman scattering (SERS). These nanocrystals are iden tified from a heterogeneous population for large optical enhancement at 647 -nm laser excitation. Second, spatially isolated single gold particles emit Stokes-shifted Raman photons in an intermittent on-and-off fashion. In con trast to population-averaged studies, blinking surface-enhanced Raman scatt ering is a signature of single-particle (or even single-molecule) behavior. By directly measuring optical enhancement and time-resolved emission on si ngle nanoparticles, this work opens new possibilities in studying the mecha nisms of SERS, in developing metal tips for near-field optical microscopy, and in designing new nanostructured materials.