Konwersatorium im. Leopolda Infelda

Continued technological progress and experimental availability of extremely powerful laser sources have opened a new era of research on laser-matter interactions. Since the ponderomotive energy of electrons driven by such radiation can now be significantly larger than the electron rest mass, it has become of interest to reexamine fundamental processes of quantum electrodynamics (QED) in high power laser pulses.

Currently available and upcoming powerful laser fields are in the femtosecond regime. Nevertheless, most theoretical predictions so far for laser-based QED processes have treated them as monochromatic plane waves. I will summarize progress in the investigation of fundamental QED processes in very intense short laser fields of relativistic power. In particular, the properties of nonlinear Compton scattering as well as the nonlinear Breit-Wheeler and Bethe-Heitler processes leading to the creation of electron-positron pairs will be discussed.