Towards controlling electron charge with nanoparticle assisted laser wakefield accelerators

TL;DR

This paper demonstrates through simulations that nanoparticle properties can be tuned to control electron beam charge in laser wakefield accelerators, providing a new method for beam manipulation.

Contribution

It introduces nanoparticle-assisted electron injection as a novel technique for controlling beam charge in laser wakefield acceleration.

Findings

Beam charge can be controlled by nanoparticle material and size.

A saturation threshold in electric field strength affects charge dependence.

Electron injection occurs over multiple plasma wave periods with varied energy spread.

Abstract

This study explores nanoparticle-assisted electron injection as a method for controlling beam charge in laser wakefield acceleration through particle-in-cell simulations. We systematically investigate how the material (Li through Au) and size (50-200 nm) of nanoparticles influence electron injection dynamics and beam charge. Our results demonstrate that beam charge (10-600 pC) can be effectively controlled by adjusting these parameters. We identify a saturation threshold in the nanoparticle electric field strength, beyond which beam charge depends on the total number of atoms in the nanoparticle rather than on the electron density after ionization. Significant electron injection occurs across multiple plasma wave periods with distribution patterns influenced by nanoparticle properties leading to increased beam charge but a broader energy spread. These findings offer practical guidelines for experimental implementation of nanoparticle-assisted injection in laser wakefield accelerators to tailor electron beam characteristics for various applications.