Attosecond-Pump Attosecond-Probe Spectroscopy at kHz Repetition Rates

The ability to perform attosecond-pump attosecond-probe spectroscopy is a long-standing goal in attosecond science. First pioneering experiments based on high-harmonic generation (HHG) [1]–[3] and at the free-electron laser LCLS [4] have demonstrated the feasibility of this technique. A widespread application of all-attosecond spectroscopy, however, has so far been hindered by the requirement to build very large setups and by the low repetition rates (10–120 Hz) of the respective laser sources.