Self-Bound Cold Atom Films, Bubbles, Tori, and Meta-Materials

Quantum droplets are Bose-Einstein condensates which are stabilized due to the effects of quantum fluctuations. We show that a variety of stable structures can be constructed from quantum droplets. The droplet can be stretched into a curved film using a quadrupolar field and can form spherical and toroidal bubbles when filled with another immiscible BEC. We also study arrays of BEC clusters stabilized inside a quantum droplet medium and show that it can form an interlocking supersolid of the droplet and the BEC. We discuss experimental procedures to create these structures. Our work serves as a blueprint for the creation of Quantum Gas Meta-Materials.