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Updated: Aug 23, 2026

Direct Imaging of Laser-driven Ultrafast Molecular Rotation
Published on: February 4, 2017
Coherent spin control of matrix isolated molecules by IR+UV laser pulses: quantum simulations for ClF in Ar
1Institut für Chemie-Physikalische und Theoretische Chemie, Freie Universität Berlin, Takustrasse 3, D-14195 Berlin, Germany. korolkov@chemie.fu-berlin.de
Abstract:
Two coherent sequential IR+UV laser pulses may be used to generate two time-dependent nuclear wave functions in electronic excited triplet and singlet states via single (UV) and two photon (IR+UV) excitation pathways, exploiting spin-orbit coupling and vibrational pre-excitation, respectively. These wave functions evolve from different Franck-Condon domains until they overlap in a domain of bond stretching with efficient intersystem crossing. Here, the coherence of the laser pulses is turned into optimal interferences of the wave packets, yielding the total wave packet at the target place, time, and with dominant target spin. The time resolution of spin control is few femtoseconds. The mechanism is demonstrated by means of quantum model simulations for ClF in an Ar matrix.
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