Our new laser system, BlastBeat, delivers two synchronized beams of 130 fs pulses at 1030 nm, with 50W average power each and a repetition rate between 166 kHz and 2 MHz. (In hardcore punk (as well as grindcore, deathcore and death and black metal), two synchronized beats played ultrafast are called a blast beat and its speed is quantified in Beats Per Minute, BPM).
We have developped a new high-harmonic generation beamline using this laser, and implemented an original and simple characterization technique to determine the absolute gas density profile in the generating medium. This has allowed us to optimize the generating conditions to reach perfect phase matching, producing a bright XUV source at 10 millions BPM (166 kHz).

Absolute gas density profiling in high-order harmonic generation
A. Comby, S. Beaulieu, E. Constant, D. Descamps, S. Petit, and Y. Mairesse, Optics Express 26, 6001