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arXiv · 1808.06872

Towards attochemistry: Control of nuclear motion through conical intersections and electronic coherences

Caroline Arnold·Oriol Vendrell·Ralph Welsch·Robin Santra
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Abstract

The effect of nuclear dynamics and conical intersections on electronic coherences is investigated employing a two-state, two-mode linear vibronic coupling model. Exact quantum dynamical calculations are performed using the multi-configuration time-dependent Hartree method (MCTDH). It is found that the presence of a non-adiabatic coupling close to the Franck-Condon point can preserve electronic coherence to some extent. Additionally, the possibility of steering the nuclear wavepackets by imprinting a relative phase between the electronic states during the photoionization process is discussed. It is found that the steering of nuclear wavepackets is possible given that a coherent electronic wavepacket embodying the phase difference passes through a conical intersection. A conical intersection close to the Franck-Condon point is thus a necessary prerequisite for control, providing a clear path towards attochemistry.

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Caroline Arnold, Oriol Vendrell, Ralph Welsch, Robin Santra. 2018-08-21. Towards attochemistry: Control of nuclear motion through conical intersections and electronic coherences. https://doi.org/10.1103/physrevlett.120.123001

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