Self-injection of electrons from evolution of wake wave

Self-injection mechanisms of plasma electrons in the self-modulated laser wakefield acceleration (SM-LWFA) are investigated. Two-dimensional (2-D) particle-in-cell (PIC) simulations show that a significant amount of plasma electrons can be self-injected into the acceleration phase of a laser wakefield by a dynamic increase of the wake wavelength in the longitudinal direction. In addition, a merging of the wake wave is observed and a large amount of electrons are self-injected to high energies. In this paper, injection phenomena are studied with 2-D simulations and a brief explanation of a new self-injection mechanism is presented.