Two-plasmon decay instability of the backscattered light of stimulated Raman scattering

The two-plasmon decay (TPD) instability of the backscattered light of the simulated Raman scattering (SRS) is first investigated with the help of one-dimensional (1D) and two-dimensional (2D) particle-in-cell (PIC) simulations. The 2D PIC simulation results show that the backscattered light of the SRS does excite TPD instability. Further, the comparison between 1D and 2D PIC simulation results shows that the backward SRS is suppressed by the excitation of TPD instability, which means the TPD instability of the scattered light could be a saturation scheme of SRS. It is also shown that, after the excitation of TPD, the electrons could experience a two-stage or even three-stage acceleration and their energy may reach to or even exceed 100 KeV, which means the TPD instability of the backscattered light could be a source of super-hot electrons. (paper)