Home

About

Advanced Search

Browse by Discipline

Scientific Societies

E-print Alerts

Add E-prints

E-print Network
FAQHELPSITE MAPCONTACT US


  Advanced Search  

 
Diagnostics of Spectrally Resolved Transient Absorption: Surface Plasmon Resonance of Metal Nanoparticles
 

Summary: Diagnostics of Spectrally Resolved Transient Absorption: Surface Plasmon Resonance of
Metal Nanoparticles
H. Ye. Seferyan, R. Zadoyan, A. W. Wark, R. M. Corn, and V. A. Apkarian*
Department of Chemistry, UniVersity of California, IrVine, California 92697-2025, and Technology and
Applications Center, Newport Corporation, 1791 Deere AVenue, IrVine, California 92606
ReceiVed: August 1, 2007; In Final Form: September 21, 2007
Time and frequency resolved transient absorption measurements yield two-dimensional images that map the
dynamical correlation between the center and width of the scattering function. Global analysis of such data
allows unique diagnostics of the mechanics underlying the time evolution. We specialize in the case of surface
plasmon resonances of optically driven nanoparticles. We present a catalog of 2D maps that can be used to
fingerprint physically meaningful cases, and we provide two experimental examples to illustrate the diagnostic
value of the maps and their utility in extracting the various time constants at play. In silver nanorods, the
experiment shows a /2 phase shift between the oscillations of the center and the width of the plasmon
resonance. Inspection of the maps allows the assignment that the center of the plasmon resonance tracks the
strain in shape-oscillations, while the width tracks the strain rate. This finding is the basis of the novel
mechanism of plasmon damping due to electron scattering from the electrophoretic potential generated by
the motion of the interfacial double layer in colloidal nanoparticles. Measurements in gold nanoparticles
show over-damped oscillations, which obscure the phase correlation between the center and width of the
plasmon. The damping is dominated by inhomogeneous dephasing, and the time dependence of the width,
which follows the temperature of the nanoparticles, and is diagnostic of the interband transition contribution

  

Source: Apkarian, V. Ara - Department of Chemistry, University of California, Irvine
Corn, Robert M.- Department of Chemistry, University of California, Irvine

 

Collections: Chemistry