We describe the ground states of a rotating two-component Bose-Einstein condensate in two dimensions. In the regime we consider, both a one-dimensional interface between the two components, and zero-dimensional interfaces (vortices) are present and contribute to the energy. The mathematical difficulty is that the two contributions are not of the same order, and thus we need to show that they somehow decouple. This requires in particular to prove a result on the localisation of the line energy for quasi-minimizers.

This joint work with Amandine Aftalion (EHESS)