Motivated by the recent observation of composite vortices in two-gap superconductors, we investigate the occurrence and stability of composite vortices in a two-component Bose condensate. As a function of the inter-component interaction strength, the vortices in the two components of the Bose mixture can overlap and form a composite vortex object. However, when two such composite vortices approach each other, their mutual interaction may cause the composite object to dissociate in its component vortices. We derive the phase diagram for the stability of composite vortices as a function of the interaction strengths of the Bose condensates, based on a variational calculation. The effective forces between the component vortices of the composite object are also derived within this approach, and allow for an interpretation of the phase diagram.Motivated by the recent observation of composite vortices in two-gap superconductors, we investigate the occurrence and stability of composite vortices in a two-component Bose condensate. As a function of the inter-component interaction strength, the vortices in the two components of the Bose mixture can overlap and form a composite vortex object. However, when two such composite vortices approach each other, their mutual interaction may cause the composite object to dissociate in its component vortices. We derive the phase diagram for the stability of composite vortices as a function of the interaction strengths of the Bose condensates, based on a variational calculation. The effective forces between the component vortices of the composite object are also derived within this approach, and allow for an interpretation of the phase diagram.

Journal of Physics Conference SeriesFeb 8, 20131 citation

Multicharged vortices stability in Bose-Einstein condensates

A. Cidrim, F. E. A. dos Santos, Vanderlei Salvador Bagnato

Abstracts BookJan 1, 20140 citations

Vorticity Knot in Two-component Bose-Einstein Condensates

Y. M. Cho

We demonstrate the existence of the helical vortex solution in two-component Bose-Einstein condensates which can be identified as a twisted vorticity flux. Based on this we argue that the recently proposed knot in two-component Bose-Einstein condensates can be interpreted as a vorticity knot, a vortex ring made of the helical vortex. This picture shows that the knot is made of two quantized vorticity fluxes linked together, whose topology $π_3(S^2)$ is fixed by the linking number of two vorticity fluxes. Due to the helical structure the knot has both topological and dynamical stability. We estimate the energy of the lightest knot to be about $3\times 10^{-3} eV$ .We demonstrate the existence of the helical vortex solution in two-component Bose-Einstein condensates which can be identified as a twisted vorticity flux. Based on this we argue that the recently proposed knot in two-component Bose-Einstein condensates can be interpreted as a vorticity knot, a vortex ring made of the helical vortex. This picture shows that the knot is made of two quantized vorticity fluxes linked together, whose topology $π_3(S^2)$ is fixed by the linking number of two vorticity fluxes. Due to the helical structure the knot has both topological and dynamical stability. We estimate the energy of the lightest knot to be about $3\times 10^{-3} eV$.

arXiv:cond-mat/0409636Sep 24, 20040 citations

Stability of quantized vortices in two-component condensates

Sam Patrick, Ansh Gupta, Ruth Gregory +1 more

Multiply quantized vortices (MQVs) within single-component Bose-Einstein condensates are unstable and decay rapidly. We show that MQVs can be stabilized by adding a small number of atoms of a second species to the vortex cores, and that these atoms remain in the vortex core as the system evolves. A consequence of the stabilization is that nearby corotating vortices can orbit in the opposite sense to their individual rotations when enough of the second species is present. This has implications concerning the imaging of vortices, as well as quantum turbulence and vortex nucleation in two-component condensates, such as those involving mixtures of $^{87}\mathrm{Rb}$ and $^{133}\mathrm{Cs}$ .Multiply quantized vortices (MQVs) within single-component Bose-Einstein condensates are unstable and decay rapidly. We show that MQVs can be stabilized by adding a small number of atoms of a second species to the vortex cores, and that these atoms remain in the vortex core as the system evolves. A consequence of the stabilization is that nearby corotating vortices can orbit in the opposite sense to their individual rotations when enough of the second species is present. This has implications concerning the imaging of vortices, as well as quantum turbulence and vortex nucleation in two-component condensates, such as those involving mixtures of $^{87}\mathrm{Rb}$ and $^{133}\mathrm{Cs}$.

Physical Review ResearchSep 20, 202314 citations

π_3(S^2)

is fixed by the linking number of two vorticity fluxes. Due to the helical structure the knot has both topological and dynamical stability. We estimate the energy of the lightest knot to be about

3\times 10^{-3} eV

^{87}\mathrm{Rb}

and

^{133}\mathrm{Cs}