Non-abelian thermal gauge potentials for high spin cold atom gases

Abstract

On the basis of the non-equilibrium Green function formalism, we derived a spinor Boltzmann equation for the Bose cold atom gases with high spin, which is achieved by a quantum Wigner transformation on the equation satisfied by the lesser Green function. After a Taylor series expansion on the scattering terms, a temperature-dependent spinor damping force can be obtained, which can be related to a non-abelian thermal gauge potential. For the spin-1 Bose gas, the thermal gauge potential constitutes a SU(3) Lie algebra. As an example, we calculate the spin coherence oscillation for the spin-1 Bose cold atom gas trapped in the optical lattice. The relative populations in the Zeeman states as well as the temperature-dependent damping force are illustrated numerically.