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arXiv · 1301.2766

Tunneling Time in Ultrafast Science is Real and Probabilistic

Alexandra Landsman·Matthias Weger·Jochen Maurer·Robert Boge·André Ludwig·Sebastian Heuser·Claudio Cirelli·Lukas Gallmann·Ursula Keller
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Abstract

We compare the main competing theories of tunneling time against experimental measurements using the attoclock in strong laser field ionization of helium atoms. Refined attoclock measurements reveal a real and not instantaneous tunneling delay time over a large intensity regime, using two different experimental apparatus. Only two of the theoretical predictions are compatible within our experimental error: the Larmor time, and the probability distribution of tunneling times constructed using a Feynman Path Integral (FPI) formulation. The latter better matches the observed qualitative change in tunneling time over a wide intensity range, and predicts a broad tunneling time distribution with a long tail. The implication of such a probability distribution of tunneling times, as opposed to a distinct tunneling time, challenges how valence electron dynamics are currently reconstructed in attosecond science. It means that one must account for a significant uncertainty as to when the hole dynamics begin to evolve.

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Alexandra Landsman, Matthias Weger, Jochen Maurer, Robert Boge, André Ludwig, Sebastian Heuser, Claudio Cirelli, Lukas Gallmann, Ursula Keller. 2013-03-17. Tunneling Time in Ultrafast Science is Real and Probabilistic. https://doi.org/10.1364/optica.1.000343

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