Electron acceleration by relativistic laser pulse on the front of solid targets

The mechanism of electron acceleration and extraction during propagation of an ultra-relativistic laser pulse in an underdense plasma in front of a solid target has been studied. When laser pulse reaches the target surface the accelerated electrons move forward inertially and gain high energy which scales proportionally to the laser intensity. The energy conversion efficiency into these electrons is ∼ne/2nc if the plasma thickness exceeds the laser pulse width. The backward electrons accelerated by the reflected light accumulate significantly higher energy though their total number is less. (author)