Theoretical study of dynamics of quantized vortices in two-dimensional two-component miscible Bose-Einstein condensates

Junsik Han, Makoto Tsubota

We study numerically the dynamics of quantized vortices in two-dimensional one-component and two-component Bose–Einstein condensates (BECs) trapped by a harmonic and box potentials. In two-component miscible BECs, we confirmed the tendency of the formation of Onsager vortices in both traps. The vortices in one component separate spatially from those in the other component, which comes from their intercomponent-coupling. We also discuss the decay of the number of vortices.

Kazushige Machida, 町田 一成

Junsik Han, Makoto Tsubota

The dynamics of quantized vortices in two-dimensional two-component miscible Bose-Einstein condensates trapped by a box potential has been numerically studied using the Gross-Pitaevskii model. We have discovered a phenomenon where the vortices of the two components spatially separate from each other, which we call the phase separation of the distribution of vortices. This phase separation occurs when the intercomponent coupling is strong. Onsager vortices, on the other hand, are formed in both components when the intercomponent coupling is weak. We distinguish between Onsager vortices and phase-separated vortices by two types of effective distances between vortices. The dependence of the transition between the Onsager vortices and phase-separated vortices on the intercomponent interaction is also studied.

Masaki Mutou, Tōru Morishita, Daisuke Kushibe +2 more

Junsik Han, Makoto Tsubota

We numerically study the dynamics of quantized vortices in two-dimensional two-component Bose-Einstein condensates (BECs) trapped by a box potential. For one-component BECs in a box potential, it is known that quantized vortices form Onsager vortices, which are clusters of same-sign vortices. We confirm that the vortices of the two components spatially separate from each other-even for miscible two-component BECs-suppressing the formation of Onsager vortices. This phenomenon is caused by the repulsive interaction between vortices belonging to different components, hence, suggesting a new possibility for vortex phase separation.

Fanghua Lin, Tai‐Chia Lin