Achieving High Efficiency And Enhanced Beam Quality In Laser Wakefield Acceleration

Laser wakefield acceleration, characterized by the extremely high electric field gradient exceeding 100 GV/m, is regarded as a compact and cost affordable technology for the next generation of particle colliders and light sources.However, it has always been a major challenge to effectively increase the energy transfer efficiency from the laser to the accelerated beam, while ensuring the beam quality remains suitable for practical applications.This study demonstrates two-step dechirping of a nanocoulomb-class accelerated electron beam using shorter laser pulses.The electron beams with an energy spread of 5% can be generated with the energy transfer efficiency of 10% to 30% in a large parameter space.For example, an electron beam with an energy of 420 MeV, a charge of 5.5 nC, and an energy spread of approximately 10% can be produced using an 8.3 J laser pulse with a duration of 7.2 fs.