Study of γ-rays, pair production, and high harmonic generation in ultra-intense laser-plasma interactions

In this thesis, we delve into the production of x-rays, γ-rays, and electron-positron pairs in plasma through particle-in-cell simulations. Our investigations revolve around γ-ray emissions in laser-solid interactions involving different target shapes and laser conditions. To enhance laser absorption by electrons and γ-rays, we propose a compact target structure scheme, which aids in improving laser conversion efficiency. We also examine the laser energy’s influence on the energy of γ-rays and pair production. We discover that bremsstrahlung is the dominant process for γ-ray emissions in high Z materials. In contrast, NCS prevails in low Z materials.