Tuning the electron energy by controlling the density perturbation position in laser plasma accelerators

TL;DR

This paper demonstrates how adjusting the position of a density perturbation in laser plasma accelerators allows precise control of electron energy, improving beam quality and enabling tunable energy outputs.

Contribution

It introduces a method to control electron energy by tuning the density perturbation position, enhancing the precision of laser plasma wakefield acceleration.

Findings

Electron energy tuned from 60 to 120 MeV

Achieved 15% energy spread with controlled injection

Produced electron beams with low divergence and charge

Abstract

A density perturbation produced in an underdense plasma was used to improve the quality of electron bunches produced in the laser-plasma wakefield acceleration scheme. Quasi-monoenergetic electrons were generated by controlled injection in the longitudinal density gradients of the density perturbation. By tuning the position of the density perturbation along the laser propagation axis, a fine control of the electron energy from a mean value of 60 MeV to 120 MeV has been demonstrated with a relative energy-spread of 15 +/- 3.6%, divergence of 4 +/- 0.8 mrad and charge of 6 +/- 1.8 pC.