Electron-positron pair creation by powerful laser-ion impact

Abstract

In view of recently achieved extreme laser powers for which the ponderomotive energy ${U}_{p}\ensuremath{\gg}2m{c}^{2}$, it has become of interest to reconsider fundamental processes of quantum electrodynamics in such powerful laser fields. In the present work, we evaluate the rates of producing electron-positron pairs by the impact of laser pulses of extreme power on highly charged ions at rest. Contrary to previous investigations, we shall consider a linearly polarized laser pulse, since at extreme laser powers the contribution of the ${A}^{2}$ part of the electromagnetic interaction becomes significant. As long as the duration of the laser pulses considered is in the femtosecond domain, the description of the laser beam by a powerful, monochromatic electromagnetic plane wave will still be justified, which simplifies considerably the calculations required.