Hamiltonian dynamics of two same-sign point vortices

摘要: We have studied numerically the Hamiltonian dynamics of two same-sign point vortices in an effectively two-dimensional, harmonically trapped Bose-Einstein condensate. found phase space system impenetrable wall that divides into distinct and exhaustive types. In two-dimensional position-coordinate space, first type corresponds to intersecting single-vortex orbits second no points common. The types are also easily distinguished spanned by radial angular velocities vortices: type, both same simple loop this whereas constitute nonintersecting loops. phase-space-dividing is from bifurcation curve rigidly rotating states Navarro et al. [Phys. Rev. Lett. 110, 225301 (2013)].