Intense few-cycle laser pulses from self-compression in a self-guiding filament

Sub-10-fs-pulses are generated by self-compression in a noble gas filament. Using input pulses from a Ti:sapphire amplifier system with an energy of about 1.5 mJ at a repetition rate of 3 kHz and a pulse duration of 30 fs self-compressed sub-10-fs pulses with energies of about 0.3 mJ have been generated. These pulses are characterized with spectral phase interferometry for direct electrical-field reconstruction (SPIDER). Depending on the laser parameters, we observe a significant change in the chirp of the white-light. The spectral distribution of the outcoming beam profile is measured to distinguish the white-light core from the surrounding halo.