Burst behavior due to the quasimode excited by stimulated Brillouin scattering in high-intensity laser-plasma interactions

The strong-coupling mode,called the"quasimode",is excited by stimulated Brillouin scattering(SBS)in high-intensity laser-plasma interactions.Also SBS of the quasimode competes with SBS of the fast mode(or slow mode)in multiion species plasmas,thus leading to a low-frequency burst behavior of SBS reflectivity.Competition between the quasimode and the ion-acoustic wave(IAW)is an important saturation mechanism of SBS in high-intensity laser-plasma interactions.These results give a clear explanation of the low-frequency periodic burst behavior of SBS and should be considered as a saturation mechanism of SBS in high-intensity laser-plasma interactions.