2015/05/08 by M. Kotur, D. Guenot, A. Jimenez-Galan +16 · 1 citation
Physics and Astronomy · #physics.atom-ph
paper · pdf · doi:10.1038/ncomms10566
5 pages, 4 figures
arxiv created 2015/05/08 · arxiv updated 2016/03/23
We study the photoionization of argon atoms close to the 3s23p6 → 3s13p64p ↔ 3s23p5 ε ℓ, ℓ=s,d Fano window resonance. An interferometric technique using an attosecond pulse train, i.e. a frequency comb in the extreme ultraviolet range, and a weak infrared probe field allows us to study both amplitude and phase of the photoionization probability amplitude as a function of photon energy. A theoretical calculation of the ionization process accounting for several continuum channels and bandwidth effects reproduces well the experimental observations and shows that the phase variation of the resonant two-photon amplitude depends on the interaction between the channels involved in the autoionization process.