Comment on “Optically Induced Damping of the Surface Plasmon Resonance in Gold Colloids”

HARTLAND, GREGORY V; HODAK, JOSÉ H; MARTINI, IGNACIO

PHYSICAL REVIEW LETTERS

Año: 1999 vol. 82 p. 2192 - 2192

0031-9007

In a recent Letter Perner et al. presented ultrafast transientabsorption data for Au particles embedded in a matrix[1]. They observed that laser excitation broadens the plasmonband of the particles, which they assigned to an increasein the electronic scattering rate. This was believedto occur because the laser heats the electron distribution,leading to Fermi edge smearing and enhanced scatteringfor states near the Fermi level [1]. The increased broadeningdecays as the electrons equilibrate with the lattice viaelectron-phonon coupling. In this Comment, we presentan alternative explanation for these results that is based onhow the dielectric constant of Au changes with electronictemperature.A Comment on the Letter by M. Perner, et al., Phys. Rev. Lett. 78, 2192 (1997). The authors of the Letter offer a Reply.