Ferrofluidity in a two-component dipolar Bose-Einstein Condensate

It is shown that the interface in a two-component Bose-Einstein condensate (BEC) in which one component exhibits a dipole-dipole interaction spontaneously forms patterns similar to those formed in a magnetic liquid subject to a magnetic field. A hexagonal pattern, hysteretic behavior, and soliton-like structure are numerically demonstrated. A phenomenon similar to the labyrinthine instability is also found. These phenomena may be realized using a 52Cr BEC. The periodic density modulation in the superfluid ground state offers evidence of supersolidity.