Self-bound crystals of antiparallel dipolar mixtures
María Arazo, A. Gallemí, M. Guilleumas, R. Mayol, L. Santos
Abstract
Recent experiments have created supersolids of dipolar quantum droplets. The resulting crystals lack, however, a genuine cohesive energy and are maintained by the presence of an external confinement, bearing a resemblance to the case of ion Coulomb crystals. We show that a mixture of two antiparallel dipolar condensates allows for the creation of potentially large, self-bound crystals, which, resembling ionic crystals in solid-state physics, are maintained by the mutual dipolar attraction between the components, with no need of transversal confinement. This opens intriguing possibilities, including three-dimensionally self-bound droplet-ring structures, stripe/labyrinthic patterns, and self-bound crystals of droplets surrounded by an interstitial superfluid, resembling the case of superfluid Helium in porous media.