Article Cite This: ACS Photonics 2018, 5, 805−813
Dynamics of Energy Transfer in Large Plasmonic Aluminum Nanoparticles Kenneth J. Smith,†,# Yan Cheng,‡,# Ebuka S. Arinze,‡,# Nicole E. Kim,‡ Arthur E. Bragg,*,† and Susanna M. Thon*,‡ †
Department of Chemistry, Johns Hopkins University, 3400 N. Charles Street, Baltimore, Maryland 21218, United States Department of Electrical and Computer Engineering, Johns Hopkins University, 3400 N. Charles Street, Baltimore, Maryland 21218, United States
‡
ACS Photonics 2018.5:805-813. Downloaded from pubs.acs.org by DURHAM UNIV on 09/06/18. For personal use only.
S Supporting Information *
ABSTRACT: We report the first photophysical characterization of energy-transfer dynamics in large (100 nm diameter) plasmonic aluminum nanoparticles suspended in liquid 2-propanol. The spectral response of the particles to ultrafast excitation is characterized by a decrease in light transmission broadly across the visible and nearinfrared on a 700 fs time scale that is consistent with predictions for electron−lattice relaxation processes. Time-dependent bleaching of the interband transitions is largely isolated from spectral changes to the intraband transition associated with light scattering and provides a window into electron−electron thermalization dynamics that complete on a ∼350 fs time scale. Subsequent relaxation in these particles is characterized by a 250 ps energy transfer to the surrounding medium, comparable to energy-transfer rates expected for much smaller particle sizes (
