Ion acceleration in multispecies targets driven by intense laser radiation pressure

TL;DR

This paper demonstrates that intense laser radiation pressure can accelerate ions from ultra-thin multispecies targets, producing narrow energy peaks and high flux, with potential for reaching over 100 MeV/nucleon energies.

Contribution

It provides experimental evidence and theoretical analysis of multispecies Radiation Pressure Acceleration in the Light Sail mode, highlighting its potential for high-energy ion beams.

Findings

Narrow band ion spectra with energies of 5-10 MeV/nucleon.

Higher flux of accelerated ions compared to previous studies.

Scaling laws suggest >100 MeV/nucleon ions are achievable with moderate improvements.

Abstract

The acceleration of ions from ultra-thin foils has been investigated using 250 TW, sub-ps laser pulses, focused on target at intensities up to $3\times10^{20} \Wcm2$. The ion spectra show the appearance of narrow band features for proton and Carbon peaked at higher energy (in the 5-10 MeV/nucleon range) and with significantly higher flux than previously reported. The spectral features, and their scaling with laser and target parameters, provide evidence of a multispecies scenario of Radiation Pressure Acceleration in the Light Sail mode, as confirmed by analytical estimates and 2D Particle In Cell simulations. The scaling indicates that monoenergetic peaks with more than 100 MeV/nucleon energies are obtainable with moderate improvements of the target and laser characteristics, which are within reach of ongoing technical developments.