Direct time-domain observation of ultrafast dephasing in adsorbate-substrate vibration under the influence of a hot electron bath: Cs adatoms on Pt(111).
The stretching vibration of Cs adsorbed on Pt(111) is excited coherently by resonant stimulated Raman excitation and its time evolution is probed by fs time-resolved second harmonic generation as a function of pump laser fluence I. As I increases, a fast dephasing component with the lifetime of tau=0.7 ps grows, being superimposed on a slow one with tau=1.9 ps. The fast component is a manifestation of pure dephasing caused by elastic and inelastic scattering of hot electrons at adsorbate.
Watanabe
Kazuya
K
Department of Photoscience, The Graduate University for Advanced Studies (SOKENDAI), Hayama, Kanagawa, 240-0193, Japan.
Takagi
Noriaki
N
Matsumoto
Yoshiyasu
Y