Non-equilibrium quantum dynamics and formation of the Bose polaron

Magnus G. Skou; Thomas G. Skov; Nils B. Jørgensen; Kristian K. Nielsen; Arturo Camacho-Guardian; Thomas Pohl; Georg M. Bruun; Jan J. Arlt

doi:10.1038/s41567-021-01184-5

arXiv · 2005.00424

Non-equilibrium quantum dynamics and formation of the Bose polaron

Magnus G. Skou·Thomas G. Skov·Nils B. Jørgensen·Kristian K. Nielsen·Arturo Camacho-Guardian·Thomas Pohl·Georg M. Bruun·Jan J. Arlt

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Abstract

Advancing our understanding of non-equilibrium phenomena in quantum many-body systems remains among the greatest challenges in physics. Here, we report on the experimental observation of a paradigmatic many-body problem, namely the non-equilibrium dynamics of a quantum impurity immersed in a bosonic environment. We use an interferometric technique to prepare coherent superposition states of atoms in a Bose-Einstein condensate with a small impurity-state component, and monitor the evolution of such quantum superpositions into polaronic quasiparticles. These results offer a systematic picture of polaron formation from weak to strong impurity interactions. They reveal three distinct regimes of evolution with dynamical transitions that provide a link between few-body processes and many-body dynamics. Our measurements reveal universal dynamical behavior in interacting many-body systems and demonstrate new pathways to study non-equilibrium quantum phenomena.

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Magnus G. Skou, Thomas G. Skov, Nils B. Jørgensen, Kristian K. Nielsen, Arturo Camacho-Guardian, Thomas Pohl, Georg M. Bruun, Jan J. Arlt. 2020-05-01. Non-equilibrium quantum dynamics and formation of the Bose polaron. https://doi.org/10.1038/s41567-021-01184-5

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