Rotating mixed He-3-He-4 nanodroplets

Mixed He-3-He-4 droplets may acquire angular momentum during their passage through the nozzle of the experimental apparatus, cooling down and undergoing isotopic segregation, developing a He-3 crust surrounding a superfluid He-4 core. Within density functional theory, we investigate their stability and the relations between their angular momenta and their shapes. We uncover a variety of behaviors where the interplay between the superfluid He-4 core and the normal-fluid He-3 coating leads to a scenario that both bears analogies with viscous rotating drops and displays new features such as configurations with a fissioned or three-lobed He-4 core, or with multiply charged vortices.