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Updated: Aug 14, 2026

Direct Imaging of Laser-driven Ultrafast Molecular Rotation
Published on: February 4, 2017
Field-free alignment of molecules observed with high-order harmonic generation
1Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan. miyazaki@iae.kyoto-u.ac.jp
Abstract:
High-order harmonic generation is demonstrated to provide a sensitive way for an extensive study of dynamic processes in the field-free alignment of strong-field-induced molecular rotational wave packets. The time-dependent harmonic signal observed from field-free-aligned N2, O2, and CO2 has been found to include two sets of beat frequency for pairs of coherently populated rotational states. One of them is the well-known frequency component characterizing the field-free alignment of molecules, and the other is ascribed to the beat that arises from coherence embedded in the wave packet. We discuss the effect of each frequency component on the revival signal observed with the harmonic generation.
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