Gamma-Flash Generation in Multi-Petawatt Laser-Matter Interactions

The progressive development of high power lasers over the last several decades, enables the study of $\gamma$-photon generation when an intense laser beam interacts with matter, mainly via inverse Compton scattering at the high intensity limit. $\gamma$-ray flashes are a phenomenon of broad interest, drawing attention of researchers working in topics ranging from cosmological scales to elementary particle scales. Over the last few years, a plethora of studies predict extremely high laser energy to $\gamma$-photon energy conversion using various target and/or laser field configurations. The aim of the present manuscript is to discuss several recently proposed $\gamma$-ray flash generation schemes, as a guide for upcoming $\gamma$-photon related experiments and for further evolution of the presently available theoretical schemes.Comment: 12 pages, 8 figure

Gamma-ray flash in the interaction of a tightly focused single-cycle ultra-intense laser pulse with a solid target

We employ the λ3 regime where a near-single-cycle laser pulse is tightly focused, thus providing the highest possible intensity for the minimal energy at a certain laser power. The quantum electrodynamics processes in the course of the interaction of an ultra-intense laser with a solid target are studied via three-dimensional particle-in-cell simulations, revealing the generation of copious γ-photons and electron–positron pairs. A parametric study of the laser polarisation, target thickness and electron number density shows that a radially polarised laser provides the optimal regime for γ-photon generation. By varying the laser power in the range of 1 to 300 PW we find the scaling of the laser to γ-photon energy conversion efficiency. The laser-generated γ-photon interaction with a high-Z target is further studied using Monte Carlo simulations revealing further electron–positron pair generation and radioactive nuclide creation