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Updated: Aug 22, 2026

Direct Imaging of Laser-driven Ultrafast Molecular Rotation
Published on: February 4, 2017
Conservation of molecular alignment for cyclic rotational wave packets in periodic pulse trains
1Instituto de Estructura de la Materia, CSIC, Serrano 121, 28006, Madrid, Spain.
Abstract:
The existence of states for which molecular alignment can be maintained for long periods of time is shown. These states, consisting of coherent superpositions of rotational states, are found among cyclic states of the generalized Floquet operator corresponding to a molecule in a short nonresonant laser pulse. For a single pulse alignment can be maintained, in some cases, for more than 40 times the pulse duration. Because of the special properties of these coherent states, arbitrarily long alignment can be achieved by using well-timed pulse trains.
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