Femtosecond Transient Reflecting Grating Methods and Analysis of the Ultrafast Carrier Dynamics on Si(111) Surfaces

Abstract

The femtosecond transient reflecting grating (TRG) method was developed and applied to monitor the ultrafast dynamics of photo-excited carriers on Si(111) surfaces. TRG responses were measured as a function of the pump beam intensity and fringe spacing, and two relaxation components were observed. An analysis of the results has suggested that the slow component corresponds to carrier diffusion and that the fast component corresponds to a combined process between ballistic transport and carrier-carrier scattering of non-equilibrium carriers.