Observation of laser power amplification in a self-injecting laser wakefield accelerator

Abstract

We report on the depletion and power ampli cation of the driving laser pulse in a strongly-driven laser wake eld accelerator. Simultaneous measurement of the transmitted pulse energy and temporal shape indicate an increase in peak power from 187 11 TW to a maximum of 318 12 TW after 13 mm of propagation in plasma density of 0 : 9 10 18 cm 3 . The power ampli cation is correlated with the injection and acceleration of electrons in the non-linear wake eld. This process is modeled by including localized redshift and subsequent group delay dispersion at the laser pulse front.