Time-resolved measurement of surface diffusion induced by femtosecond laser pulses

Diffusion of atomic oxygen on a vicinal Pt111 surface induced by femtosecond laser pulses has been studied using optical second-harmonic generation as a sensitive in situ probe of the step coverage. Time-resolved studies of the hopping rate for step-terrace diffusion with a two-pulse correlation scheme reveal a time constant of 1.5 ps for the energy transfer from the electronic excitation of the substrate to the frustrated translations of the adsorbate.