Fig. 2: Identification of the electron injection, acceleration and betatron oscillation processes.
From: High-flux bright x-ray source from femtosecond laser-irradiated microtapes
a Electron density (green-yellow) and longitudinal field Ex (blue-red) at t = − 16T0, in which `A', `B' and `C' mark three different electron nanobunches in space, but can also be used to phenomenologically represent the compression, injection and acceleration stages of the same electron bunch over time. b Transverse field Ey at t = − 16T0. c Longitudinal field Ex at t = 12.5T0 and electron phase space (black-yellow dots), while (d) shows the transverse field Fy and the electron density distribution (green-yellow), where the electron density below y < 0.6λ and ne < 5nc are removed to clearly show the Fy. The inset is a zoom-in. In (c), the dashed cyan line demarcates the surface plasma wave (SPW)-dominated region (below) from the diffracted wave-dominated (above). e Comparison of the transverse profile of the SPW model (red dashed) and Ex (black) from the PIC simulation, extracted from the vertical black dashed line marked in (c). f The 1D profiles of ne (blue), Fy (black) and the potential (red) obtained from (d).
