Highly efficient laser-driven Compton gamma-ray source

Abstract

The recent advancement of high-intensity lasers has made all-optical Compton scattering become a promising way to produce ultrashort brilliant γ -rays in an ultra-compact system. However, so far achieved Compton γ -ray sources are limited by low conversion efficiency and spectral intensity. Here we present a highly efficient gamma photon emitter obtained by irradiating a high-intensity laser pulse on a miniature plasma device consisting of a plasma lens and a plasma mirror. This concept exploits strong spatiotemporal laser-shaping process and high-charge electron acceleration process in the plasma lens, as well as an efficient nonlinear Compton scattering process enabled by the plasma mirror. Our full three-dimensional particle-in-cell simulations demonstrate that in this novel scheme, brilliant γ -rays with very high conversion efficiency (higher than 10 ^−2 ) and spectral intensity (∼10 ^9 $\mathrm{photons}/0.1 \% \mathrm{BW}$ ) can be achieved by employing currently available petawatt-class lasers with intensity of 10 ^21 W cm ^−2 . Such efficient and intense γ -ray sources would find applications in wide-ranging areas.

Keywords

• laser–plasma interaction
• relativistic self-focusing
• nonlinear Compton scattering
• gamma-ray sources
• particle-in-cell simulations