Dense blocks of energetic ions driven by multi-petawatt lasers

TL;DR

This paper presents a novel scheme using multi-petawatt lasers and density-modulated targets to produce dense, high-quality ion beams suitable for fusion and high energy density applications, demonstrated through simulations.

Contribution

It introduces a new method combining density-modulated targets and substrate embedding to enhance ion beam yield and quality in laser-driven acceleration.

Findings

Ions can be uniformly accelerated to 25% of light speed.

The scheme produces dense ion blocks suitable for fusion ignition.

Simulations show effective acceleration at 10^22 W/cm^2 laser intensity.

Abstract

Laser-driven ion accelerators have the advantages of compact size, high density, and short bunch duration over conventional accelerators. Nevertheless, it is still challenging to simultaneously enhance the yield and quality of laser-driven ion beams for practical applications. Here we propose a scheme to address this challenge via the use of emerging multi-petawatt lasers and a density-modulated target. The density-modulated target permits its ions to be uniformly accelerated as a dense block by laser radiation pressure. In addition, the beam quality of the accelerated ions is remarkably improved by embedding the target in a thick enough substrate, which suppresses hot electron refluxing and thus alleviates plasma heating. Particle-in-cell simulations demonstrate that almost all ions in a solid-density plasma of a few microns can be uniformly accelerated to about 25% of the speed of light by a laser pulse at an intensity around 1022 W/cm2. The resulting dense block of energetic ions may drive fusion ignition and more generally create matter with unprecedented high energy density.