title: Dynamics of Interacting Fermions in Spin-Dependent Potentials.
abstract: Recent experiments with dilute trapped Fermi gases observed that weak interactions can drastically modify spin transport dynamics and give rise to robust collective effects including global demagnetization, macroscopic spin waves, spin segregation, and spin self-rephasing. In this Letter, we develop a framework for studying the dynamics of weakly interacting fermionic gases following a spin-dependent change of the trapping potential which illuminates the interplay between spin, motion, Fermi statistics, and interactions. The key idea is the projection of the state of the system onto a set of lattice spin models defined on the single-particle mode space. Collective phenomena, including the global spreading of quantum correlations in real space, arise as a consequence of the long-ranged character of the spin model couplings. This approach achieves good agreement with prior measurements and suggests a number of directions for future experiments.
authors.affiliation: Department of Physics, University of Colorado, Boulder, Colorado 80309, USA.|JILA, NIST, Center for Theory of Quantum Matter, University of Colorado, Boulder, Colorado 80309, USA.
authors.forename: Andrew P
authors.initials: AP
authors.lastname: Koller
authors.affiliation: JILA, NIST, Center for Theory of Quantum Matter, University of Colorado, Boulder, Colorado 80309, USA.
authors.forename: Michael L
authors.initials: ML
authors.lastname: Wall
authors.affiliation: Department of Mathematics and Statistics, Swarthmore College, 500 College Avenue, Swarthmore, Pennsylvania 19081, USA.
authors.forename: Josh
authors.initials: J
authors.lastname: Mundinger
authors.affiliation: Department of Physics, University of Colorado, Boulder, Colorado 80309, USA.|JILA, NIST, Center for Theory of Quantum Matter, University of Colorado, Boulder, Colorado 80309, USA.
authors.forename: Ana Maria
authors.initials: AM
authors.lastname: Rey