Stability properties of vortex states in trapped two-dimensional Bose condensate

Summary form only given.The study of the properties of vortices is one of the major subfields of superfluidity. In helium II, it has been shown that a hydrodynamic instability involving vortex lines can be caused by counterflow along the lines, an effect involving the interplay between normal and super-fluids. Here, we present a study on the stability property of the vortex states of a condensate confined in a two-dimensional harmonic spherical potential at zero temperature. Our work does not take the thermal atoms into account, but instead focuses on the intrinsic coupling between vortex states.