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arXiv · 1105.6369

Metastability in Spin-Polarized Fermi Gases

Y. A. Liao·M. Revelle·T. Paprotta·A. S. C. Rittner·Wenhui Li·G. B. Partridge·R. G. Hulet
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Abstract

We study the role of particle transport and evaporation on the phase separation of an ultracold, spin-polarized atomic Fermi gas. We show that the previously observed deformation of the superfluid paired core is a result of evaporative depolarization of the superfluid due to a combination of enhanced evaporation at the center of the trap and the inhibition of spin transport at the normal-superfluid phase boundary. These factors contribute to a nonequilibrium jump in the chemical potentials at the phase boundary. Once formed, the deformed state is highly metastable, persisting for times of up to 2 s.

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Y. A. Liao, M. Revelle, T. Paprotta, A. S. C. Rittner, Wenhui Li, G. B. Partridge, R. G. Hulet. 2011-09-19. Metastability in Spin-Polarized Fermi Gases. https://doi.org/10.1103/physrevlett.107.145305

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