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arXiv · 2509.15853

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

Oliver Mathiak·Lars Reichwein·Alexander Pukhov
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Abstract

We investigate the process of creating electron-positron pairs from laser-matter interaction in pre-ionised 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 is 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.

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Oliver Mathiak, Lars Reichwein, Alexander Pukhov. 2025-09-19. Electron-positron pair generation using a single kJ-class laser pulse in a foam-reflector setup. https://doi.org/10.1063/5.0317574

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