Electron–positron pair generation using a single kJ-class laser pulse in a foam–reflector setup

We investigate the process of creating electron–positron pairs from laser–matter interaction in pre-ionized foam targets using particle-in-cell simulations. A high-intensity laser pulse drives electrons via direct laser acceleration up to a cone-shaped reflector. The high-energy electrons interact with the reflected laser pulse, generating abundant pairs. The effects of the plasma-channel shape on the propagation of the laser pulse and subsequent pair production are studied. The results show that the number of Compton emission and Breit–Wheeler pair creation events is highly sensitive to the diffraction of the laser due to its interaction with the foam.