紧聚焦的飞秒激光脉冲在真空中对电子的加速

研究了紧聚焦的圆偏振飞秒相对论高斯激光脉冲与电子的相互作用，提出了一种激光加速电子的新机制.利用束腰小、强度大的激光脉冲上升沿加速电子，束腰大、强度小的脉冲下降沿减速电子，当光脉冲和电子分离时，电子获得了能量增益.研究发现，初始静止的电子与强度高于10¹⁹Wμm^{2/cm2的光脉冲作用以后，可以获得MeV量级的能量.初始位于焦点附近的电子被加速的效果较好，而远离焦点的电子几乎不能获得能量增益. 关键词： 电子加速 能量增益 高斯脉冲 束腰}

Electron acceleration by a tightly focused femtosecond laser beam in vacuum

Ponderomotive-force driven acceleration of an electron at the focus of a high-intensity short-pulse laser is considered using a model that the electrons accelerated are near the focus but decelerated far away the focus. For intensities above 10¹⁹Wμm^{2/cm2, the electron's energy gain in the range of MeV can be realized when the electron leaves the laser pulse. Final energy gain of the electron as a function of its initial position has also been discussed. We find that an electron initially near the focus can be accelerated well.}