Laser-dressed photoionization for the temporal characterization of attosecond pulses generated from plasma mirrors

We report on the implementation of a laser-dressed photoionization method aimed at measuring the temporal structure of high-order harmonics generated from plasma mirrors at the attosecond timescale. Using numerical simulations, we show that the infrared dressing pulse induces up-down asymmetry on the angular distribution of photoelectrons. Experimentally single-shot photoelectron spectra with angular resolution were successfully detected with a velocity-map imaging spectrometer. However, the impact of the infrared dressing field in the photoelectron spectra could not be observed. We discuss several issues that potentially hampered these observations and suggest corresponding setup improvements.

Automated summary

We implemented a laser-dressed photoionization method to measure the temporal structure of high-order harmonics from plasma mirrors at the attosecond scale. Numerical simulations showed that the infrared dressing pulse caused up-down asymmetry in the angular distribution of photoelectrons. Although we successfully detected single-shot photoelectron spectra with angular resolution using a velocity-map imaging spectrometer, we could not observe the impact of the infrared dressing field in the spectra. We discuss various issues that may have hindered these observations and suggest improvements to the setup.