Generation of GeV protons from 1 PW laser interaction with near critical density targets

TL;DR

This paper demonstrates through simulations that a 1 PW laser interacting with near-critical density targets can accelerate protons up to 1.3 GeV, revealing new insights into laser-driven ion acceleration mechanisms.

Contribution

The study introduces new scaling laws and optimal conditions for proton acceleration using ultra-intense laser pulses on near-critical density targets.

Findings

Protons up to 1.3 GeV are achievable with 1 PW lasers.

Magnetic fields and electric fields play key roles in ion acceleration.

Scaling laws help optimize proton energy output.

Abstract

The propagation of ultra intense laser pulses through matter is connected with the generation of strong moving magnetic fields in the propagation channel as well as the formation of a thin ion filament along the axis of the channel. Upon exiting the plasma the magnetic field displaces the electrons at the back of the target, generating a quasistatic electric field that accelerates and collimates ions from the filament. Two-dimensional Particle-in-Cell simulations show that a 1 PW laser pulse tightly focused on a near-critical density target is able to accelerate protons up to an energy of 1.3 GeV. Scaling laws and optimal conditions for proton acceleration are established considering the energy depletion of the laser pulse.