In this paper, nonlinear laser energy absorption in a finite-size electron–positron–ion plasma is studied in detail, using a two-dimensional relativistic electromagnetic PIC simulation code. It turns out that the laser energy absorption rate in the electron–positron–ion plasma drastically depends on the positron to electron density ratio ( ##IMG## [http://ej.iop.org/images/1555-6611/30/9/096002/lpaba9ddieqn1.gif] {$\alpha = {n_p}/{n_e}$} ). This can be attributed to the effects of this parameter on nonlinear phenomena related to laser absorption such as phase mixing and laser scattering. The results illustrate that phase-mixing time is reduced by increasing the defined density ratio, resulting in the enhancement of the laser energy absorption rate. As a significant result, it can be found that in a finite-size electron–positron–ion plasma the absorption rate increases with increasing ##IMG## [http://ej.iop.org/images/1555-6611/...] {$\alpha $}

中文翻译：

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有限尺寸电子-正电子-离子等离子体中大功率激光脉冲对粒子的激励

在本文中，使用二维相对论电磁PIC仿真代码详细研究了在有限尺寸的电子-正离子离子等离子体中的非线性激光能量吸收。事实证明，电子-正电子-离子等离子体中的激光能量吸收率完全取决于正电子与电子的密度比（## IMG ## [http://ej.iop.org/images/1555-6611/30 /9/096002/lpaba9ddieqn1.gif] {$ \ alpha = {n_p} / {n_e} $}）。这可以归因于该参数对与激光吸收有关的非线性现象的影响，例如相位混合和激光散射。结果表明，通过增加定义的密度比可以减少相混合时间，从而提高激光能量吸收率。结果是，