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arXiv · 1701.06352

Phase-Resolved Two-Dimensional Spectroscopy of Electronic Wavepackets by Laser-Induced XUV Free Induction Decay

Samuel Beaulieu·Etienne Bloch·Lou Barreau·Antoine Comby·Dominique Descamps·Romain Géneaux·Francois Légaré·Stéphane Petit·Yann Mairesse
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Abstract

We present a novel time- and phase-resolved, background-free scheme to study the extreme ultraviolet dipole emission of a bound electronic wavepacket, without the use of any extreme ultraviolet exciting pulse. Using multiphoton transitions, we populate a superposition of quantum states which coherently emit extreme ultraviolet radiation through free induction decay. This emission is probed and controlled, both in amplitude and phase, by a time-delayed infrared femtosecond pulse. We directly measure the laser-induced dephasing of the emission by using a simple heterodyne detection scheme based on two-source interferometry. This technique provides rich information about the interplay between the laser field and the Coulombic potential on the excited electron dynamics. Its background-free nature enables us to use a large range of gas pressures and to reveal the influence of collisions in the relaxation process.

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Samuel Beaulieu, Etienne Bloch, Lou Barreau, Antoine Comby, Dominique Descamps, Romain Géneaux, Francois Légaré, Stéphane Petit, Yann Mairesse. 2017-03-21. Phase-Resolved Two-Dimensional Spectroscopy of Electronic Wavepackets by Laser-Induced XUV Free Induction Decay. https://doi.org/10.1103/physreva.95.041401

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