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تسجيل مستخدم جديدCharacterizing multielectron dynamics during recollision
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Measuring the delay for an electron to emerge from different states is one of the major achievements of attosecond science. This delay can have two origins - the electron wave packet is reshaped during departure by the electrostatic field of the ionizing medium or it is modified by dynamic interaction with the remaining electrons. Most experiments have observed the former, but confirmation requires a complex calculation. A direct measurement of multielectron dynamics is needed. Photo-recombination - the inverse of photoionization - occurs naturally during electron recollision and can be measured by combining a perturbing beam to modify the recollision electron before recombination. These in situ methods allow us to unambiguously isolate multielectron dynamics - the reference being the spectral phase of an attosecond pulse simultaneously measured in spectral regions without multielectron interaction. Here, we measure the group delay of the recollision electron caused by plasmonic resonance dynamics in Xe, simulate the in situ measured spectral phase of a recollision electron generated in the presence of the plasmonic resonance in C$_{60}$ and present a corresponding semi-classical theory based on the strong-field approximation. Our results suggest that in situ techniques, together with 300 eV recollision electrons, will allow the ultimate time response of electronic matter to be measured.
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When intense light irradiates a quantum system, an ionizing electron recollides with its parent ion within the same light cycle and, during that very brief (few femtosecond) encounter, its kinetic energy sweeps from low to high energy and back. There
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