Two-color above threshold ionization of helium and xenon has been used to analyze the synchronization between individual pulses of the femtosecond extreme ultraviolet (XUV) free electron laser in Hamburg and an independent intense mode-locked Ti:sapphire laser. Characteristic sidebands appear in the photoelectron spectra when the two pulses overlap spatially and temporally. The cross-correlation curve points to a rms jitter between the two sources at the experiment. A more precise determination of the temporal fluctuation between the XUV and infrared pulses is obtained through the analysis of the single-shot sideband intensities.
REFERENCES
The simulation was performed by solving the time-dependent Schrödinger equation for a “single active electron” xenon atom with a laser intensity of .
