Plasma-based laser pulse control techniques for laser wakefield accelerators

Possible plasma-based techniques for controlling or modifying the laser pulse in a laser wakefield accelerator (LWFA) are examined, using laser propagation simulation codes. Laser pulse shortening or chopping prior to injection into a plasma guiding channel occurs when the peak laser power is slightly above the critical power for relativistic focusing. A channel-guided LWA may undergo further compression due to relativistic modulation effects. Multi-stage capillary discharges allow the channel density to be extended and tapered for optimal acceleration in future LWFA experiments.