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arXiv · 1202.6564

High-polarization limit of the quasi-two-dimensional Fermi gas

Jesper Levinsen·Stefan K. Baur
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Abstract

We demonstrate that the theoretical description of current experiments of quasi-2D Fermi gases requires going beyond usual 2D theories. We provide such a theory for the highly spin-imbalanced quasi-2D Fermi gas. For typical experimental conditions, we find that the location of the recently predicted polaron-molecule transition is shifted to lower values of the vacuum binding energy due to the interplay between transverse confinement and many-body physics. The energy of the attractive polaron is calculated in the 2D-3D crossover and displays a series of cusps before converging towards the 3D limit. The repulsive polaron is shown to be accurately described by a 2D theory with a single interaction parameter.

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Jesper Levinsen, Stefan K. Baur. 2012-02-29. High-polarization limit of the quasi-two-dimensional Fermi gas. https://doi.org/10.1103/physreva.86.041602

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