We present a table-top beamline providing a soft X-ray supercontinuum extending up to 370 eV from high-order harmonic generation with sub-13 fs 1300 nm driving pulses and simultaneous production of sub-5 fs pulses centered at 800 nm. Optimization of high harmonic generation in a long and dense gas medium yields a photon flux of similar to 1.4 x 10(6) photons/s/1% bandwidth at 300 eV. The temporal resolution of X-ray transient absorption experiments with this beamline is measured to be 11 fs for 800 nm excitation. This dual-wavelength approach, combined with high flux and high spectral and temporal resolution soft X-ray absorption spectroscopy, is a new route to the study of ultrafast electronic dynamics in carbon-containing molecules and materials at the carbon K-edge.

Springer Nature
Sci. Rep
High-Harmonic Generation and EUV Science

Barreau, L., Ross, A., Garg, S., Kraus, P., Neumark, D., & Leone, S. (2020). Efficient table-top dual-wavelength beamline for ultrafast transient absorption spectroscopy in the soft X-ray region. Sci. Rep, 10(1), 5733: 1–9. doi:10.1038/s41598-020-62461-6