著者

Shivaram Niranjan Timmers Henry Tong Xiao-Min Sandhu Arvinder

出版者

Elsevier B.V.

雑誌

Chemical physics (ISSN:03010104)

巻号頁・発行日

vol.414, pp.139-148, 2013-03

被引用文献数

7

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We present experimental results and a theoretical framework for understanding the ionization dynamics in atoms exposed to XUV attosecond pulse trains and strong multi-cycle infrared (IR) fields. We invoke the Floquet formalism to model dressed atomic states as a manifold of Fourier components spaced by the laser frequency. In XUV-IR pump–probe measurements, we observe that the ionization yield oscillates due to quantum interference between photo-excitation paths to a Floquet state. We show that the intensity-dependent shifts of atomic structure modify the ionization channels and the associated interference phase. We extract this phase variation and compare it with simulations. These results provide a comprehensive description of the two-color ionization process and enable new schemes for control of attosecond ionization and fragmentation dynamics.