Dominance of Radiation Pressure in Ion Acceleration with Linearly Polarized Pulses at Intensities of $10^{21}\textrm{W}\textrm{cm}^{-2}$

TL;DR

This paper introduces a new ion acceleration regime driven by radiation pressure at lower laser intensities than previously thought, producing monoenergetic ion beams through a hybrid Light-Sail/TNSA process.

Contribution

It demonstrates that radiation pressure can dominate ion acceleration at $10^{21} extrm{Wcm}^{-2}$, enabling monoenergetic ion beams via a hybrid acceleration mechanism.

Findings

Achieved 1.26 GeV monoenergetic carbon ion beams.

Identified conditions for radiation pressure dominance in hybrid acceleration.

Showed lower intensity thresholds for radiation pressure-driven ion acceleration.

Abstract

A novel regime is proposed where, employing linearly polarized laser pulses at intensities $10^{21}\textrm{Wcm}^{-2}$ as two order of magnitude lower than earlier predicted [T. Esirkepov et al., Phys. Rev. Lett. 92, 175003 (2004)], ions are dominantly accelerated from ultrathin foils by the radiation pressure, and have monoenergetic spectra. In the regime, ions accelerated from the hole-boring process quickly catch up with the ions accelerated by target normal sheath acceleration (TNSA), and they then join in a single bunch, undergoing a hybrid Light-Sail/TNSA acceleration. Under an appropriate coupling condition between foil thickness, laser intensity and pulse duration, laser radiation pressure can be dominant in this hybrid acceleration. Two-dimensional PIC simulations show that $1.26\textrm{GeV}$ quasimonoenergetic $\textrm{C}^{6+}$ beams are obtained by linearly polarized laser pulses at intensities of $10^{21}\textrm{Wcm}^{-2}$.