Massive vortices in a binary mixture of Bose-Einstein condensates
Andrea Richaud, Vittorio Penna, M. Guilleumas, R. Mayol
Abstract
We thoroughly analyze a notable class of states peculiar to a bosonic repulsive binary mixture loaded in a rotating box-like circular trap, i.e. states where vortices in one species host the atoms of the other species, which thus play the role of massive cores. Within a fully-analytic framework, we calculate the equilibrium distance distinguishing the motion of precession of two corotating massive vortices, the angular momentum of each condensed species, the vortices healing length and the cores characteristic size. We then compare these previsions with the measures extracted from the numerical solutions of the associated coupled Gross-Pitaevskii equations. Interestingly, making use of a suitable change of reference frame, we show that the vortices drag the massive cores which they host thus conveying them their same motion of precession, but there is no evidence of quantum viscous friction between the two fluids, since the cores keep their orientation constant while orbiting.