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arXiv · 2004.05010

Attosecond-resolved photoionization of chiral molecules

Samuel Beaulieu·Antoine Comby·Alex Clergerie·Jérémie Caillat·Dominique Descamps·Nirit Dudovich·Baptiste Fabre·Romain Géneaux·François Légaré·Stéphane Petit·Bernard Pons·Gil Porat·Thierry Ruchon·Richard Taïeb·Valérie Blanchet·Yann Mairesse
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Abstract

Chiral light-matter interactions have been investigated for two centuries, leading to the discovery of many chiroptical processes used for discrimination of enantiomers. Whereas most chiroptical effects result from a response of bound electrons, photoionization can produce much stronger chiral signals that manifest as asymmetries in the angular distribution of the photoelectrons along the light propagation axis. Here we implement a self-referenced attosecond photoelectron interferometry to measure the temporal profile of the forward and backward electron wavepackets emitted upon photoionization of camphor by circularly polarized laser pulses. We found a delay between electrons ejected forward and backward, which depends on the ejection angle and reaches 24 attoseconds. The asymmetric temporal shape of electron wavepackets emitted through an autoionizing state further reveals the chiral character of strongly-correlated electronic dynamics.

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Samuel Beaulieu, Antoine Comby, Alex Clergerie, Jérémie Caillat, Dominique Descamps, Nirit Dudovich, Baptiste Fabre, Romain Géneaux, François Légaré, Stéphane Petit, Bernard Pons, Gil Porat, Thierry Ruchon, Richard Taïeb, Valérie Blanchet, Yann Mairesse. 2020-04-10. Attosecond-resolved photoionization of chiral molecules. https://doi.org/10.1126/science.aao5624

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