Abstract

The excitation of an electron-hole plasma with an ultrashort intense laser pulse is characterized by a sensitive interplay between the generation of the coherent interband polarization, its decay and the generation of nonequilibrium carrier distributions and their relaxation. For sub-picosecond pulses the microscopic processes during the excitation are controlled by the carrier screening. The screened interaction of a single carrier with the surrounding e-h plasma can be understood as a scattering process with the excited plasmons. These microscopic scattering processes are responsible for the dephasing of polarization as well as for the carrier relaxation. In this sense they fix the intrinsic time scale of the excitation.

© 1996 IEEE