Interparticle electromagnetic coupling in assembled gold-necklace nanoparticles
Abbreviated Journal Title
J. Am. Chem. Soc.
DENDRIMER-METAL NANOCOMPOSITES; ELECTRON RELAXATION DYNAMICS; OPTICAL-PROPERTIES; ORGANIC DENDRIMERS; SPECTROSCOPY; NANOCRYSTALS; CHROMOPHORES; ENHANCEMENT; CATALYSIS; DEVICES; Chemistry, Multidisciplinary
A unique phenomenon of interparticle electromagnetic coupling in closely spaced gold nanoparticles has been observed by probing the ultrafast electron dynamics of spherical gold nanoparticles with those of a gold-necklace nanoparticle system. Electron-electron scattering and electron-phonon relaxation (two main aspects of electron dynamics) are found to be significantly different for gold-necklace particles when compared to spherical gold nanoparticles. On inter band gap excitation, appreciably slower and pump-power independent electron-electron scattering has been observed for necklace particles (similar to 500 fs for Au-neck compared to similar to 200 fs for Au-spherical nanoparticles). Significantly slower pump-power dependent electron-phonon relaxation has also been observed for the necklace particle system. The electron dynamics for gold-necklace particles is quite unique, and existing models of electron-electron scattering and electron-phonon relaxation were unsuccessful in explaining the dynamics in this system. The results are thus explained by incorporating efficient dipolar electronic coupling between the neighboring nanoparticles.
Journal of the American Chemical Society
"Interparticle electromagnetic coupling in assembled gold-necklace nanoparticles" (2007). Faculty Bibliography 2000s. 7552.