Attosecond spectral shearing interferometry.
We show that the complete characterization of arbitrarily short isolated attosecond x-ray pulses can be achieved by applying spectral shearing interferometry to photoelectron wave packets. These wave packets are coherently produced through the photoionization of atoms by two time-delayed replicas of the x-ray pulse, and are shifted in energy with respect to each other by simultaneously applying a strong laser field. The x-ray pulse is reconstructed with the algorithm developed for optical pulses, which requires no knowledge of ionization physics. Using a 800-nm shearing field, x-ray pulses shorter than approximately 400 asec can be fully characterized.
Quéré
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Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, Ontario, Canada K1A 0R6.
Itatani
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J
Yudin
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GL
Corkum
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PB