Scissor-cross ionization injection in laser wakefield accelerators

TL;DR

This paper introduces a novel ionization injection method in laser wakefield accelerators using a frequency-doubled pulse at an angle, resulting in high-quality electron beams with controllable properties.

Contribution

The study presents a new collision-based ionization injection scheme that improves injection quality and beam control in laser wakefield acceleration.

Findings

Produced electron beams of ~500 MeV energy

Achieved ~1% energy spread and low emittance

Demonstrated control over charge and energy spread

Abstract

We propose to use a frequency doubled pulse colliding with the driving pulse at an acute angle to trigger ionization injection in a laser wakefield accelerator. This scheme effectively reduces the duration that injection occurs, thus high injection quality is obtained. Three-dimensional particle-in-cell simulations show that electron beams with energy of ~500 MeV, charge of ~40 pC, energy spread of ~1% and normalized emittance of a few millimeter milliradian can be produced by ~100 TW laser pulses. By adjusting the angle between the two pulses, the intensity of the trigger pulse and the gas dope ratio, the charge and energy spread of the electron beam can be controlled.