Influences of sinusoidal density modulation on stimulated Raman scattering in inhomogeneous plasmas

摘要: The influence of sinusoidal density modulation on the stimulated Raman scattering (SRS) reflectivity in inhomogeneous plasmas is studied by three-wave coupling equations, fully kinetic Vlasov simulations and particle cell (PIC) simulations. Through numerical solution we find that capable inducing absolute SRS even though Rosenbluth gain smaller than {\pi}, give a region modulational wavelength amplitude can be induced, which agrees with early studies. average obtained has same trend growth rate equations. Instead causing instability, shorter basic length able to suppress inflation through harmonic waves. And, PIC qualitatively agree our Our results offer an alternative explanation high at underdense plasma experiments, due long-wavelength modulation, potential method using short-wavelength modulation.