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arXiv · 1102.5472

Dynamical properties of a trapped dipolar Fermi gas at finite temperature

J. -N. Zhang·R. -Z. Qiu·L. He·S. Yi
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Abstract

We investigate the dynamical properties of a trapped finite-temperature normal Fermi gas with dipole-dipole interaction. For the free expansion dynamics, we show that the expanded gas always becomes stretched along the direction of the dipole moment. In addition, we present the temperature and interaction dependences of the asymptotical aspect ratio. We further study the collapse dynamics of the system by suddenly increasing the dipolar interaction strength. We show that, in contrast to the anisotropic collapse of a dipolar Bose-Einstein condensate, a dipolar Fermi gas always collapses isotropically when the system becomes globally unstable. We also explore the interaction and temperature dependences for the frequencies of the low-lying collective excitations.

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J. -N. Zhang, R. -Z. Qiu, L. He, S. Yi. 2011-02-27. Dynamical properties of a trapped dipolar Fermi gas at finite temperature. https://doi.org/10.1103/physreva.83.053628

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