Far-from-equilibrium dynamics of angular momentum in a quantum many-particle system

Igor N. Cherepanov; Giacomo Bighin; Lars Christiansen; Anders Vestergaard Jørgensen; Richard Schmidt; Henrik Stapelfeldt; Mikhail Lemeshko

arXiv · 1906.12238

Far-from-equilibrium dynamics of angular momentum in a quantum many-particle system

Igor N. Cherepanov·Giacomo Bighin·Lars Christiansen·Anders Vestergaard Jørgensen·Richard Schmidt·Henrik Stapelfeldt·Mikhail Lemeshko

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Abstract

We use laser-induced rotation of single molecules embedded in superfluid helium nanodroplets to reveal angular momentum dynamics and transfer in a controlled setting, under far-from-equilibrium conditions. As an unexpected result, we observe pronounced oscillations of time-dependent molecular alignment that have no counterpart in gas-phase molecules. Angulon theory reveals that these oscillations originate from the unique rotational structure of molecules in He droplets and quantum-state-specific transfer of rotational angular momentum to the many-body He environment on picosecond timescales. Our results pave the way to understanding collective effects of macroscopic angular momentum exchange in solid state systems in a bottom-up fashion.

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Igor N. Cherepanov, Giacomo Bighin, Lars Christiansen, Anders Vestergaard Jørgensen, Richard Schmidt, Henrik Stapelfeldt, Mikhail Lemeshko. 2019-06-28. Far-from-equilibrium dynamics of angular momentum in a quantum many-particle system. https://arxiv.org/abs/1906.12238

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