Effects of relativistic electron temperature on parametric instabilities for intense laser propagation in underdense plasma

Abstract

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Effects of large laser bandwidth on stimulated Raman scattering instability in underdense plasma

“…At this temperature, the linear growth rate of the SRS does not yet change considerably by the electron temperature. 26 However, at high electron temperatures, the fluctuation fields in plasma become higher. These fluctuations and large-number electrons near the phase velocity of plasma wave allow the SRS instability to grow the nonlinear stage in a shorter time, which cannot be suppressed by the laser bandwidth.…”

“…25,26 The corresponding wave vector is k ¼ k 1 þ jk 2 j ¼ 0:98 which is normalized by x 0 /c, where k 1 is the wave vector of the backscattering light at the first time and k 2 is the wave vector of the backscattering light at the second time. This is shown later in Fig.…”

Stimulated Raman scattering in a non-eigenmode regime

“…In the following, we consider the relativistic modification of the SRS non-eigenmode in hot plasma. The dispersion of SRS under the relativistic intensity laser is [9,25]…”

“…In the density region n e 0.25n c , the electrostatic wave is the eigenmode of the electron plasma wave. Relativistic intensity lasers can reduce the effective electron plasma frequency, and therefore eigenmode SRS may develop at n e > 0.25n c [25] . In this work, we show the presence of non-eigenmode SRS, which is found at plasma density n e > 0.25n c even without considering the relativistic effect.…”

Plasma modulator for high-power intense lasers

“…Stimulated Raman scattering (SRS), the decay of the incident laser into a scattered light and an electron plasma wave [26,27], is an important mechanism in plasma optics [28], and also one of the key concerns in ICF [1,3,29]. SRS in the relativistic regime is described by the following dispersion relation [30,31]…”