Femtosecond investigation of electron thermalization in gold
Journal
Physical Review B
Journal Volume
48
Journal Issue
16
Pages
12365-12368
Date Issued
1993
Author(s)
Abstract
Electron-electron and electron-phonon thermalization processes are investigated in gold films using a high-sensitivity multiple-wavelength femtosecond pump-probe technique. A nonequilibrium electron distribution is excited by free-carrier absorption of an infrared femtosecond pulse and its relaxation dynamics followed by measuring the transient reflectivity and transmissivity with a visible probe pulse. Measurements performed in a thin gold film in the very low perturbation limit (Te20 K) yield evidence for the existence of a non-Fermi electron distribution with an electron thermalization time of 500 fs and an electron-lattice interaction time of 1 ps. The apparent thermalization dynamics of the electron gas is much faster in optically thick samples and is shown to be dominated by transport effects. © 1993 The American Physical Society.
SDGs
Type
journal article