The influence of relativistic‐ponderomotive nonlinearities and the plasma inhomogeneity on the nonlinear interaction between a high‐power laser beam and a warm underdense plasma are studied. It is clear that the relativistic ponderomotive force and the electron temperature modify the electron density distribution and consequently change the dielectric permittivity of the plasma. Therefore, by presenting the modified electron density and the nonlinear dielectric permittivity of the warm plasma, the electromagnetic wave equation for the propagation of intense laser beam through the plasma is derived. This nonlinear equation is numerically solved and the distributions of electromagnetic fields in the plasma, the variations of electron density, and plasma refractive index are investigated for two different background electron density profiles. The results show that the amplitude of the electric field and electron density oscillations gradually increase and decrease, during propagation in the inhomogeneous warm plasma with linear and exponential density profiles, respectively, and the distribution of electron density becomes extremely sharp in the presence of intense laser beam. It is also indicated that the electron temperature and initial electron density have an impact on the propagation of the laser beam in the plasma and change the plasma refractive index and the oscillations' amplitude and frequency. The obtained results indicate the importance of a proper choice of laser and plasma parameters on the electromagnetic field distributions, density steepening, and plasma refractive index variations in the interaction of an intense laser beam with an inhomogeneous warm plasma.

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相对论和质动力非线性对高功率激光束与非均匀热等离子体相互作用的影响

研究了相对论-桥脑动力的非线性和等离子体的不均匀性对高功率激光束与温暖的密集等离子体之间的非线性相互作用的影响。显然，相对论质动力和电子温度改变了电子密度分布，并因此改变了等离子体的介电常数。因此，通过给出热等离子体的修正的电子密度和非线性介电常数，可以得出用于强激光束通过等离子体传播的电磁波方程。对该非线性方程进行了数值求解，并针对两种不同的背景电子密度曲线研究了等离子体中电磁场的分布，电子密度的变化以及等离子体折射率。结果表明，在具有线性和指数密度分布的不均匀热等离子体中传播期间，电场和电子密度振荡的振幅逐渐增大和减小，并且在强激光的存在下电子密度的分布变得极其尖锐。光束。还表明，电子温度和初始电子密度会影响等离子体中激光束的传播，并改变等离子体的折射率以及振荡的幅度和频率。获得的结果表明正确选择激光和等离子体参数对激光束的重要性。分别在具有线性和指数密度分布的不均匀暖等离子体中传播时，电子束的分布在强激光束的作用下变得非常尖锐。还表明，电子温度和初始电子密度会影响激光束在等离子体中的传播，并改变等离子体的折射率以及振荡的幅度和频率。获得的结果表明正确选择激光和等离子体参数对激光束的重要性。分别在具有线性和指数密度分布的不均匀暖等离子体中传播时，电子束的分布在强激光束的作用下变得非常尖锐。还表明，电子温度和初始电子密度会影响等离子体中激光束的传播，并改变等离子体的折射率以及振荡的幅度和频率。获得的结果表明正确选择激光和等离子体参数对激光束的重要性。还表明，电子温度和初始电子密度会影响等离子体中激光束的传播，并改变等离子体的折射率以及振荡的幅度和频率。获得的结果表明正确选择激光和等离子体参数对激光束的重要性。还表明，电子温度和初始电子密度会影响等离子体中激光束的传播，并改变等离子体的折射率以及振荡的幅度和频率。获得的结果表明正确选择激光和等离子体参数对激光束的重要性。强激光束与不均匀热等离子体相互作用中的电磁场分布，密度变陡和等离子体折射率变化。