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arXiv · 2310.11570

Quantum control of ro-vibrational dynamics and application to light-induced molecular chirality

Monika Leibscher·Eugenio Pozzoli·Alexander Blech·Mario Sigalotti·Ugo Boscain·Christiane P. Koch
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Abstract

Achiral molecules can be made temporarily chiral by excitation with electric fields, in the sense that an average over molecular orientations displays a net chiral signal [Tikhonov et al., Sci. Adv. 8, eade0311 (2022)]. Here, we go beyond the assumption of molecular orientations to remain fixed during the excitation process. Treating both rotations and vibrations quantum mechanically, we identify conditions for the creation of chiral vibrational wavepackets -- with net chiral signals -- in ensembles of achiral molecules which are initially randomly oriented. Based on the analysis of symmetry and controllability, we derive excitation schemes for the creation of chiral wavepackets using a combination of (a) microwave and IR pulses and (b) a static field and a sequence of IR pulses. These protocols leverage quantum rotational dynamics for pump-probe spectroscopy of chiral vibrational dynamics, extending the latter to regions of the electromagnetic spectrum other than the UV.

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Monika Leibscher, Eugenio Pozzoli, Alexander Blech, Mario Sigalotti, Ugo Boscain, Christiane P. Koch. 2023-10-17. Quantum control of ro-vibrational dynamics and application to light-induced molecular chirality. https://doi.org/10.1103/physreva.109.012810

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