The theory of the terahertz (THz) waves emission from a near-critical plasma slab under the action of the focused p-polarized laser pulse is developed. The spectral, angular and energy characteristics of the THz signal are studied as functions of the focusing degree and the incidence angle of laser radiation, as well as the density and thickness of the plasma slab. It is shown that the extremely strong increase in the energy of the THz signal (up to millijoule level) and conversion rate (up to 10 %) occurs at the almost normal incidence of the ultra-short, tightly focused p-polarized laser pulse on the thin plasma slab with the near-critical density and rare electron collisions.

中文翻译：

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p偏振激光辐射作用下近临界等离子体板发射太赫兹脉冲

近临界等离子体板在聚焦作用下发射太赫兹波的理论p- 开发出偏振激光脉冲。研究了太赫兹信号的光谱、角度和能量特性，作为激光辐射的聚焦度和入射角以及等离子体板的密度和厚度的函数。结果表明，太赫兹信号的能量（高达毫焦耳级）和转换率（高达 10%）在超短、紧密聚焦的近乎正入射的情况下出现极强的增加。p- 薄等离子体板上的偏振激光脉冲具有近临界密度和罕见的电子碰撞。