Generation of 500 MeV-1 GeV energy electrons from laser wakefield acceleration via ionization induced injection using CO_2 mixed in He

摘要

Laser wakefield acceleration of 500 MeV to 1 GeV electron bunches has been demonstrated using ionization injection in mixtures of 4% to 10% of CO_2 in He. 80 TW laser pulses were propagated through 5 mm gas jet targets at electron densities of 0.4 - 1.5 × 10~(19)cm~(-3). Ionization injection led to lower density thresholds, a higher total electron charge, and an increased probability of producing electrons above 500 MeV in energy compared to self-injection in He gas alone. Electrons with GeV energies were also observed on a few shots and indicative of an additional energy enhancement mechanism.