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Ultrafast Dynamics of Gold-Based Nanocomposite Materials



Joseph S. Melinger, V D. Kleiman, D McMorrow, Franziska Grohn, Barry J. Bauer, Eric J. Amis


The ultrafast electron dynamics are investigated for small ((2.5 4.0) nm average diameter) Au nanoparticles contained in two different types of organic-inorganic nanocomposites. In one case, an aqueous solution contains Au nanoparticles embedded inside polyamidoamine (PAMAM) dendrimers. In the other case, hexanethiol-passivated (HT) Au nanoparticles are suspended in dichloromethane solution. Femtosecond two-color pump-probe spectroscopy is used to excite and probe the dynamics of the Au nanoparticles in the region of the surface plasmon resonance. The transient response is measured as a function of laser excitation fluence (Joules/cm2). For the metal-dendrimer nanocomposites, the transient response consists of a single exponential decay that relaxes with a timeconstant of less than 1.2 ps, and is due mainly to electron-phonon coupling. The relaxation timescale shows a weak dependence on the size of the Au nanoparticle embedded inside the dendrimer, and a weak dependence on excitation fluence.
Journal of Physical Chemistry A
No. 18


Au, dendrimer, nanoparticles, nanoposites, ultrafast dynamics


Melinger, J. , Kleiman, V. , McMorrow, D. , Grohn, F. , Bauer, B. and Amis, E. (2003), Ultrafast Dynamics of Gold-Based Nanocomposite Materials, Journal of Physical Chemistry A, [online], (Accessed July 13, 2024)


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Created April 30, 2003, Updated October 12, 2021