Anomalous Spin segregation in a weakly interacting two-component Fermi gas

Abstract

We explain the spin segregation seen at Duke in a two-component gas of 6Li [Du, Luo, Clancy and Thomas, Phys. Rev. Lett. 101,150401 (2008)] as a mean-field effect describable via a collisionless Boltzmann equation. As seen in experiments, we find that slight differences in the trapping potentials in the two spin states drive small spin currents. Hartree-Fock type interactions convert these currents into a redistribution of populations in energy space, and consequently a long lived spin texture develops. We explore the interaction strength dependence of these dynamics, finding close agreement with experiment.Comment: 4 pages, 3 figures, published version. Text modified to include qualitative discussion of spin-segregation effect; 1 figure adde