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arXiv · 0909.4917

Correlated versus Ferromagnetic State in Repulsively Interacting Two-Component Fermi Gases

Hui Zhai
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Abstract

Whether a spin-1/2 Fermi gas will become ferromagnetic as the strength of repulsive interaction increases is a long-standing controversial issue. Recently this problem is studied experimentally by Jo et al, Science, 325, 1521 (2009) in which the authors claim a ferromagnetic transition is observed. This work is to point out the results of this experiment can not distinguish whether the system is in a ferromagnetic state or in a non-magnetic but strongly short-range correlated state. A conclusive experimental demonstration of ferromagnetism relies on the observation of ferromagnetic domains.

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Hui Zhai. 2009-09-27. Correlated versus Ferromagnetic State in Repulsively Interacting Two-Component Fermi Gases. https://doi.org/10.1103/physreva.80.051605

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