Quantitative Studies of Vortex Decay in Finite Temperature Atomic Condensates

An off-centered vortex in a pure harmonically-trapped atomic condensate precesses at constant radius, as recently confirmed experimentally (D.V. Freilich \emph{et al.} Science 329, 1182 (2010).). The thermal cloud induces a frictional force on the vortex, thereby leading it to a gradual decay. Extending earlier work (B. Jackson \emph{et al.} Phys. Rev. A 79, 053615 (2009).), we perform a detailed quantitative study of the role of the dynamics of the thermal cloud on the motion of one or more vortices; we model the system by a dissipative Gross-Pitaevskii equation for the condensate, self-consistently coupled to a quantum Boltzmann equation for the thermal modes (Zaremba-Nikuni-Griffin formalism).