Analytical Sciences

Abstract − Analytical Sciences, 16(4), 403 (2000).

Femtosecond Transient Reflecting Grating Methods and Analysisof the Ultrafast Carrier Dynamics on Si(111) Surfaces
Tomohiro MORISHITA,* Akihide HIBARA,* Tsuguo SAWADA,* Isao TSUYUMOTO,**and Akira HARATA***
*Department of Applied Chemistry, School of Engineering, The University of Tokyo,Hongo, Bunkyo, Tokyo 113-8656, Japan
**Department of Environmental Systems Engineering, Kanazawa Institute of Technology,Ohgigaoka, Nonoichi, Ishikawa 921-8501,Japan
***Department of Molecular Science and Technology, Graduate School of Engineering Science,Kyushu University, Kasugakoen, Kasuga, Fukuoka 816-8580, Japan
The femtosecond transient reflecting grating (TRG) method was developed and applied to monitor the ultrafast dynamicsof photo-excited carriers on Si(111) surfaces. TRG responses were measured as a function of the pump beam intensityand fringe spacing, and two relaxation components were observed. An analysis of the results has suggested that the slowcomponent corresponds to carrier diffusion and that the fast component corresponds to a combined process betweenballistic transport and carrier-carrier scattering of non-equilibrium carriers.