Figure 2
From: Dephasingless laser wakefield acceleration in the bubble regime
The ultrafast flying focus and electron acceleration in a bubble-regime dephasingless laser wakefield accelerator. (a) Schematic of the optical configuration for an accelerating focus, including the axiparabola and echelon. For illustrative purposes, the optics are shown in transmission, but experiments would likely be performed in reflection30. (b) The accelerator geometry showing the on-axis amplitude \(a_0\) and inner-core spot size \(w_0\) of the masked laser pulse—simulated in vacuum (solid) and plasma (dashed)—along with the designed focal velocity in the plasma \(\beta _{\rm{f}}\) (dot-dashed). (c) Energy gain of the ionization-injected electrons in the first bubble. After 20 dephasing lengths, 25 pC of charge was accelerated up to 2.1 GeV.
