Attosecond streaking of soft-X-ray pulses generated by a mid-IR laser

Summary form only given. Attosecond metrology has so far remained limited to Ti:Sa lasers combined with an active stabilization of the carrier-envelope phase (CEP), where the achievable photon energy is limited to ~100eV. This is too low to access X-ray absorption edges of most second- and third-row elements which are central to chemistry, biology and material science. The quadratic scaling of the ponderomotive energy with wavelength enables to generate photon energies in the soft-X-ray (SXR) domain with mid-IR laser sources. We use our commercial TiSa laser system (5mJ, 1kHz) to generate 1.8μm mid-IR pulses with an OPA (TOPAS HE, conversion efficiency 34%), which is spectrally broadened to an octave in a static filled hollow core fiber delivering pulse energies of up to 540 μJ. Recompression to the few-cycle regime is performed by a pair of fused-silica wedges. A fraction of the beam is used to measure the CEP stability with a single-shot stereo-ATI phase meter. The CEP stability was found to be better than 300 mrad rms, remarkably better than most previously reported values [1].We use our commercial TiSa laser system (5mJ, 1kHz) to generate 1.8μm mid-IR pulses with an OPA (TOPAS HE, conversion efficiency 34%), which is spectrally broadened to an octave in a static filled hollow core fiber delivering pulse energies of up to 540PJ. Recompression to the few-cycle regime is performed by a pair of fused-silica wedges. A fraction of the beam is used to measure the CEP stability with a single-shot stereo-ATI phase meter. The CEP stability was found to be better than 300 mrad rms, remarkably better than most previously reported values [1].