Femtosecond Four-Wave Mixing with Dense Plasmas.

The screened Coulomb-phonon quantum kinetics is applied to the twopulse excitation of femtosecond four-wave mixing (FWM). The time-resolved FWM shows, both in theory and experiment, a characteristic photon echo structure. From the analysis of the theoretical and experimental time-integrated signal, a dephasing time is obtained which varies with the inverse cubic power of the plasma density. Finally, FWM with coherent control yields in theory and experiment coherent plasmon-phonon mixed mode quantum beats. [ABSTRACT FROM AUTHOR]