title: Short-time spin dynamics in strongly correlated few-fermion systems.
abstract: The nonequilibrium spin dynamics of a one-dimensional system of repulsively interacting fermions is studied by means of density-matrix renormalization group simulations. We focus on the short-time decay of the oscillation amplitudes of the centers of mass of spin-up and spin-down fermions. Because of many body effects, the decay is found to evolve from quadratic to linear in time, and eventually back to quadratic as the strength of the interaction increases. The characteristic rate of the decay increases linearly with the strength of repulsion in the weak-coupling regime, while it is inversely proportional to it in the strong-coupling regime. Our predictions can be tested in experiments on tunable ultracold few-fermion systems in one-dimensional traps.
authors.affiliation: NEST, Scuola Normale Superiore and Istituto di Nanoscienze-CNR, I-56126 Pisa, Italy.
authors.forename: Sebastiano
authors.initials: S
authors.lastname: Peotta
authors.forename: Davide
authors.initials: D
authors.lastname: Rossini
authors.forename: Pietro
authors.initials: P
authors.lastname: Silvi
authors.forename: G
authors.initials: G
authors.lastname: Vignale
authors.forename: Rosario
authors.initials: R
authors.lastname: Fazio
authors.forename: Marco
authors.initials: M
authors.lastname: Polini