High quality electron bunch generation using a longitudinal density-tailored plasma-based accelerator in the three-dimensional blowout regime

TL;DR

This paper presents a theoretical and simulation study of a plasma accelerator technique that produces high-brightness, low-energy-spread electron bunches by tailoring plasma density profiles in the three-dimensional blowout regime.

Contribution

It uncovers the physical mechanism behind high-quality electron generation and demonstrates how driver intensity and plasma scale-length influence beam quality.

Findings

Potential to produce beams with peak brightnesses of 10^20 to 10^21 A/m^2/rad^2

Achieves absolute energy spreads of about 0.3 MeV

Validates the concept with particle-in-cell simulations using existing laser and electron beam drivers.

Abstract

The generation of very high quality electron bunches (high brightness and low energy spread) from a plasma-based accelerator in the three-dimensional blowout regime using self-injection in tailored plasma density profiles is analyzed theoretically and with particle-in-cell simulations. The underlying physical mechanism that leads to the generation of high quality electrons is uncovered by tracking the trajectories of the electrons as they cross the sheath and are trapped by the wake. Details on how the intensity of the driver and the density scale-length of the plasma control the ultimate beam quality are described. Three-dimensional particle-in-cell simulations indicate that this concept has the potential to produce beams with peak brightnesses between $10^{20}$ and $10^{21}$ $\mathrm{A}/\mathrm{m}^2/\mathrm{rad}^2$and with absolute projected energy spreads of $\sim 0.3~\mathrm{MeV}$ using existing lasers or electron beams to drive nonlinear wakefields.