Effective interaction in an unbalanced Fermion mixture

Christian Recher; Heinerich Kohler

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arXiv · 1306.6377

Effective interaction in an unbalanced Fermion mixture

Christian Recher·Heinerich Kohler

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Abstract

A one dimensional Fermi mixture with delta--interaction is investigated in the limit of extreme imbalance. In particular we consider the cases of only one or two minority Fermions which interact with the Fermi-sea of the majority Fermions. We calculate dispersion relation and polaron mass for the minority Fermions as well as equal time density-density correlators. Within a cluster expansion we derive an expression for the effective interaction potential between minority Fermions. For our calculations we use a reformulation of the exact wave functions, originally obtained by Yang and Gaudin by a nested Bethe ansatz, in terms of determinants.

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Christian Recher, Heinerich Kohler. 2013-06-26. Effective interaction in an unbalanced Fermion mixture. https://arxiv.org/abs/1306.6377

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