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Sub-laser-cycle electron pulses for probing molecular dynamics

Naturevolume 417pages917922 (2002) | Download Citation



Experience shows that the ability to make measurements in any new time regime opens new areas of science. Currently, experimental probes for the attosecond time regime (10-18–10-15 s) are being established. The leading approach is the generation of attosecond optical pulses by ionizing atoms with intense laser pulses. This nonlinear process leads to the production of high harmonics during collisions between electrons and the ionized atoms. The underlying mechanism implies control of energetic electrons with attosecond precision. We propose that the electrons themselves can be exploited for ultrafast measurements. We use a ‘molecular clock’, based on a vibrational wave packet in H2+ to show that distinct bunches of electrons appear during electron–ion collisions with high current densities, and durations of about 1 femtosecond (10-15 s). Furthermore, we use the molecular clock to study the dynamics of non-sequential double ionization.

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F.L. acknowledges financial support from Canada's Natural Science and Engineering Research Council, the Canadian Institute for Photonics Innovation and Quebec's Fonds pour la Formation des Chercheurs et l'Aide à la Recherche.

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  1. National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario, K1A OR6, Canada

    • Hiromichi Niikura
    • , R. Hasbani
    • , Misha Yu. Ivanov
    • , D. M. Villeneuve
    •  & P. B. Corkum
  2. Université de Sherbrooke, Sherbrooke, PQ, Canada

    • F. Légaré
    •  & A. D. Bandrauk


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The authors declare that they have no competing financial interests.

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Correspondence to P. B. Corkum.

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