Efficient ion acceleration and dense electron-positron plasma creation in ultra-high intensity laser-solid interactions

Abstract

The radiation pressure of next generation ultra-high intensity (> 10 23 W/cm 2 ) lasers could efficiently accelerate ions to GeV energies. However, nonlinear quantumelectrodynamic effects play an important role in the interaction of these laser pulses with matter. Here we show that these effects may lead to the production of an extremely dense (∼ 10 24 cm −3 ) pair-plasma which absorbs the laser pulse consequently reducing the accelerated ion energy and laser to ion conversion efficiency by up to 30-50% & 50-65%, respectively. Thus we identify the regimes of laser-matter interaction, where either ions are efficiently accelerated to high energy or dense pair-plasmas are produced as a guide for future experiments.

Spin polarization of electrons by ultraintense lasers

“…The important strong-field QED processes in lasercreated QED plasmas are [2,7,8]: (i) incoherent emission of > ∼ MeV energy gamma-ray photons by electrons and positrons on acceleration by the macroscopic electromagnetic fields in the laser-produced plasma (strongly nonlinear Compton scattering), with the resulting radiationreaction strongly modifying the dynamics of the emitting electron or positron [9,10]; (ii) pair creation by the emitted gamma-ray photons, in the same electromagnetic fields (the multi-photon Breit-Wheeler process [11]). For example: non-linear Compton scattering and the resulting radiation can lead to almost complete laser absorption [12,13]; pair cascades (where pairs emit further gamma-ray photons, which generate even more pairs), can lead to the creation of critical density pair plasmas [14][15][16][17]. It is therefore essential that we correctly include these QED processes in our models of the interaction of next-generation laser pulses with matter.…”