High-Intensity QED with Ultra-short Laser Pulses and XFEL’s

Optical high-intensity lasers with pulse durations of tens of femtoseconds and intensities up to 10^22 W/cm^2 allow to investigate non-linear effects in Quantum Electrodynamics (QED).

In my talk I will discuss the process of photon emission by electrons when interacting with high-intensity laser pulses, focussing on the influence of the ultra-short pulse duration. In particular I will show how the spectral broadening caused by the short pulse duration can be mitigated. This will help improve the spectral brightness of laser-based
X- and gamma-ray sources.

In addition I will present results on laser-assisted X-ray Compton scattering, where the X-rays from an XFEL are synchronously scattered with an intense laser pulse. The Compton-scattered X-rays show a complex spectrum with features representing the laser-driven electron states.