Laser-Ion Lens and Accelerator

TL;DR

This paper introduces the laser-ion lensing and acceleration (LILA) concept, demonstrating a method to focus and accelerate ions using ultra-intense laser pulses and shaped targets, validated through simulations, with potential for high-energy ion beams.

Contribution

The paper presents the novel LILA technique combining laser-ion focusing and acceleration, supported by simple models and 3D simulations, advancing high-energy ion beam generation.

Findings

Stable focusing regimes identified across various laser powers.

Predicted ion energies exceeding 750 MeV.

Achieved high ion density and energy density at focus.

Abstract

Generation of highly collimated monoenergetic relativistic ion beams is one of the most challenging and promising areas in ultra-intense laser-matter interactions because of the numerous scientific and technological applications that require such beams. We address this challenge by introducing the concept of laser-ion lensing and acceleration (LILA). Using a simple analogy with a gradient-index lens, we demonstrate that simultaneous focusing and acceleration of ions is accomplished by illuminating a shaped solid-density target by an intense laser pulse at ~10^22 W/cm^2 intensity, and using radiation pressure of the laser to deform/focus the target into a cubic micron spot. We show that the LILA process can be approximated using a simple deformable mirror model, and then validate it using three-dimensional particle-in-cell simulations of a two-species plasma target comprised of electrons and ions. Extensive scans of the laser and target parameters identify the stable propagation regime where the Rayleigh-Taylor (RT)-like instability is suppressed. Stable focusing are found at different laser powers (from few- to multi-petawatt). Focused ion beams with the focused density of order 10^23 cm^-3, energies in access of 750MeV, and energy density up to 2*10^13 J/cm^3 at the focal point are predicted for future multi-petawatt laser systems.