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arXiv · 1404.5761

Ultracold atom-electron interaction: from two to many-body physics

Anita Gaj·Alexander T. Krupp·Jonathan B. Balewski·Robert Löw·Sebastian Hofferberth·Tilman Pfau
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Abstract

The transition from a few-body system to a many-body system can result in new length scales, novel collective phenomena or even in a phase transition. Such a threshold behavior was shown for example in 4He droplets, where 4He turns into a superfluid for a specific number of particles [1]. A particularly interesting question in this context is at which point a few-body theory can be substituted by a mean field model, i. e. where the discrete number of particles can be treated as a continuous quantity. Such a transition from two non-interacting fermionic particles to a Fermi sea was demonstrated recently [2]. In this letter, we study a similar crossover to a many-body regime based on ultralong-range Rydberg molecules [3] forming a model system with binary interactions.

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Anita Gaj, Alexander T. Krupp, Jonathan B. Balewski, Robert Löw, Sebastian Hofferberth, Tilman Pfau. 2014-04-23. Ultracold atom-electron interaction: from two to many-body physics. https://doi.org/10.1038/ncomms5546

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