Temperature dependence of seed pulse amplitude and density grating in Brillouin amplification

Abstract

Seed pulse dynamics as well as plasma response during Brillouin amplification are investigated in the so called strong coupling regime. Due to the finite amplitudes trapping of electrons and ions may become important. These effects are not covered by the commonly used three-wave interaction equations derived from fluid theory. Therefore, here investigations based on a Vlasov model are presented. The kinetic calculations show that the density response is not as predicted by the fluid models. We find a pronounced density grating with significant particle trapping. The influence of the latter on the seed amplitude development is discussed in dependence on the electron and ion temperatures.