Interaction of parametric instabilities from 3<i>ω</i> and 2<i>ω</i> lasers in large-scale inhomogeneous plasmas

Abstract

The mechanism of energy transfer from 3ω pump light to stimulated Brillouin scattering (SBS) generated by 2ω pump light is proposed. The backscattering light of stimulated Raman scattering (SRS) generated by 3ω pump light can work as a seed of the SBS of 2ω pump light, which results in the increase of the latter. Adding 2ω pump light into 3ω pump light will decrease the reflectivity of SBS generated from 3ω pump light. The total reflectivity will first decrease and then increase with an increase of the ratio of 2ω light intensity to the intensity of 2ω and 3ω lights , and will be controlled in a lower level when this ratio f is about 10%−20%. These results give a method to control the total reflectivity of SBS and SRS in inertial confinement fusion (ICF) by adding 2ω light into 3ω light.