# Ultrahigh charge electron beams from laser-irradiated solid surface

## TL;DR

This paper demonstrates a method to generate highly collimated, high-charge, quasi-monoenergetic electron beams with MeV energies using laser interaction with solid targets, promising for dense matter applications.

## Contribution

It introduces a novel laser-solid interaction scheme that produces high-charge, well-collimated electron beams with unique spectral and density properties, supported by particle-in-cell simulations.

## Key findings

- Electron beams with divergence of a few degrees and charge around 100 nC.
- Beams have quasi-monoenergetic spectra peaked at MeV energies.
- Energy density in high-Z materials reaches ~10^{12} J/m^3.

## Abstract

Compact acceleration of a tightly collimated relativistic electron beam with high charge from a laser-plasma interaction has many unique applications. However, currently the well-known schemes, including laser wakefield acceleration from gases and vacuum laser acceleration from solids, often produce electron beams either with low charge or with large divergence angles. In this work, we report the generation of highly collimated electron beams with a divergence angle of a few degrees, quasi-monoenergetic spectra peaked at the MeV level, and extremely high charge ($\sim$100 nC) via a powerful sub-ps laser pulse interacting with a solid target in grazing incidence. Particle-in-cell simulations illustrate a new direct laser acceleration scenario, in which the self-filamentation is triggered in a large-scale near-critical-density plasma and electron bunches are accelerated periodically and collimated by the ultra-intense electromagnetic field. The energy density of such electron beams in high-Z materials reaches to $\sim10^{12} \mathrm{J/m^{3}}$, making it a promising tool to drive warm or even hot dense matter states.