GeV laser ion acceleration from ultrathin targets: The laser break-out afterburner

TLDR

Other ion‑acceleration techniques require laser intensities of 10^24 W/cm² or higher, 2–3 orders of magnitude above any demonstrated system. The newly identified Laser Break‑out Afterburner (BOA) mechanism accelerates carbon ions to >2 GeV at 10^21 W/cm², surpassing target‑normal sheath acceleration in energy and efficiency and producing quasi‑monoenergetic bunches with median energies exceeding recent experimental results.

Abstract

A new laser-driven ion acceleration mechanism has been identified using particle-in-cell (PIC) simulations. This mechanism allows ion acceleration to GeV energies at vastly reduced laser intensities compared with earlier acceleration schemes. The new mechanism, dubbed “Laser Break-out Afterburner” (BOA), enables the acceleration of carbon ions to greater than 2 GeV energy at a laser intensity of only 10 21 W/cm 2 , an intensity that has been realized in existing laser systems. Other techniques for achieving these energies in the literature rely upon intensities of 10 24 W/cm 2 or above, i.e., 2–3 orders of magnitude higher than any laser intensity that has been demonstrated to date. Also, the BOA mechanism attains higher energy and efficiency than target normal sheath acceleration (TNSA), where the scaling laws predict carbon energies of 50 MeV/u for identical laser conditions. In the early stages of the BOA, the carbon ions accelerate as a quasi-monoenergetic bunch with median energy higher than that realized recently experimentally.