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arXiv · 1105.5997

Dynamical spin-flip susceptibility for a strongly interacting ultracold Fermi gas

Matteo Sandri·Anna Minguzzi·Flavio Toigo
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Abstract

The Stoner model predicts that a two-component Fermi gas at increasing repulsive interactions undergoes a ferromagnetic transition. Using the random-phase approximation we study the dynamical properties of the interacting Fermi gas. For an atomic Fermi gas under harmonic confinement we show that the transverse (spin-flip) dynamical susceptibility displays a clear signature of the ferromagnetic phase in a magnon peak emerging from the Stoner particle-hole continuum. The dynamical spin susceptibilities could be experimentally explored via spin-dependent Bragg spectroscopy.

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Matteo Sandri, Anna Minguzzi, Flavio Toigo. 2011-05-30. Dynamical spin-flip susceptibility for a strongly interacting ultracold Fermi gas. https://doi.org/10.1209/0295-5075%2F96%2F66004

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