Spin Drag and Spin-Charge Separation in Cold Fermi Gases

Abstract

Low-energy spin and charge excitations of one-dimensional interacting fermions are completely decoupled and propagate with different velocities. These modes however can decay due to several possible mechanisms. In this paper we expose a new facet of spin-charge separation: not only the speeds but also the damping rates of spin and charge excitations are different. While the propagation of long-wavelength charge excitations is essentially ballistic, spin propagation is intrinsically damped and diffusive. We suggest that cold Fermi gases trapped inside a tight atomic waveguide offer the opportunity to measure the spin-drag relaxation rate that controls the broadening of a spin packet.

4 pages, 4 figures, submitted

References in corpus (2)

• Spin-charge separation in cold Fermi-gases: a real time analysis
• Charge and spin dynamics of interacting Fermions in a one dimensional harmonic trap

Cited by in corpus (5)

• Fulde-Ferrell-Larkin-Ovchinnikov superfluidity in one-dimensional optical lattices
• Collisional Properties of a Polarized Fermi Gas with Resonant Interactions
• Collective excitations in one-dimensional ultracold Fermi gases: a comparative study
• Spin-drag relaxation time in one-dimensional spin-polarized Fermi gases
• Time-dependent current-density-functional theory of spin-charge separation and spin drag in one-dimensional ultracold Fermi gases