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arXiv · 1304.8099

Few interacting fermions in one-dimensional harmonic trap

Tomasz Sowiński·Tobias Grass·Omjyoti Dutta·Maciej Lewenstein
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Abstract

We study spin-1/2 fermions, interacting via a two-body contact potential, in a one-dimensional harmonic trap. Applying exact diagonalization, we investigate their behavior at finite interaction strength, and discuss the role of the ground-state degeneracy which occurs for sufficiently strong repulsive interaction. Even low temperature or a completely depolarizing channel may then dramatically influence the system's behavior. We calculate level occupation numbers as signatures of thermalization, and we discuss the mechanisms to break the degeneracy.

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Tomasz Sowiński, Tobias Grass, Omjyoti Dutta, Maciej Lewenstein. 2013-09-06. Few interacting fermions in one-dimensional harmonic trap. https://doi.org/10.1103/physreva.88.033607

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