Spin waves in a one-dimensional spinor Bose gas

J. N. Fuchs 1, D. M. Gangardt 2, T. Keilmann 3, G. V. Shlyapnikov 2, 4

Physical Review Letters 95 (2005) 150402

We study a one-dimensional (iso)spin 1/2 Bose gas with repulsive delta-function interaction by the Bethe Ansatz method and discuss the excitations above the polarized ground state. In addition to phonons the system features spin waves with a quadratic dispersion. We compute analytically and numerically the effective mass of the spin wave and show that the spin transport is greatly suppressed in the strong coupling regime, where the isospin-density (or ``spin-charge\'\') separation is maximal. Using a hydrodynamic approach, we study spin excitations in a harmonically trapped system and discuss prospects for future studies of two-component ultracold atomic gases.

  • 1. Laboratoire de Physique des Solides (LPS),
    CNRS : UMR8502 – Université Paris XI - Paris Sud
  • 2. Laboratoire de Physique Théorique et Modèles Statistiques (LPTMS),
    CNRS : UMR8626 – Université Paris XI - Paris Sud
  • 3. Max-Planck-Institut für Quantenoptik,
    Max-Planck-Institut
  • 4. Van der Waals-Zeeman Institute,
    University of Amsterdam