  The dynamics of quantized vortices in two-dimensional two-component miscible
Bose-Einstein condensates (BECs) trapped by a box potential has been
numerically studied using the Gross{ Pitaevskii model. We have discovered a
novel 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 inter-component coupling is
strong. Onsager vortices, on the other hand, are formed in both components when
the inter-component 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 inter-component interaction is also studied.

Quantum Gases