Droplets and Supersolids

Ratheejit Ghosh, Chinmayee Mishra, Luis Santos +1 more

Gases of doubly dipolar particles, with both magnetic and electric dipole moments, offer intriguing novel possibilities. We show that the interplay between doubly dipolar interactions, quantum stabilization, and external confinement results in a rich ground-state physics of supersolids and incoherent droplet arrays in doubly dipolar condensates. Our study reveals novel possibilities for engineering quantum droplets and droplet supersolids, including supersolid-supersolid transitions and the realization of supersolid arrays of pancake droplets.

Christophe Josserand, Yves Pomeau A, Sergio Rica

Xuefeng Zhang, Yuchuan Wen, Sebastian Eggert

Albert Gallemí, Luis Santos

Recent breakthrough experiments on dipolar condensates have reported the creation of supersolids, including two-dimensional arrays of quantum droplets. Droplet arrays are, however, not the only possible nontrivial density arrangement resulting from the interplay of mean-field instability and quantum stabilization. Several other possible density patterns may occur in trapped condensates at higher densities, including the so-called honeycomb supersolid, a phase that exists, as it is also the case of a triangular droplet supersolid, in the thermodynamic limit. We show that compared to droplet supersolids, honeycomb supersolids have a much-enhanced superfluid fraction while keeping a large density contrast, and constitute in this sense a much better dipolar supersolid. However, in contrast to droplet supersolids, quantized vortices cannot be created in a honeycomb supersolid without driving a transition into a so-called labyrinthic phase. We show that the reduced moment of inertia, and with it the superfluid fraction, can be however reliably probed by studying the dynamics following a scissorslike perturbation.

Yves Couder, Suzie Protière, Emmanuel Fort +1 more

K. Mukherjee, S. M. Reimann

We investigate the classicality of linear dipolar droplet arrays through a normal mode analysis of the dynamical properties in comparison to the supersolid regime. The vibrational patterns of isolated-droplet crystals that time-evolve after a small initial kick closely follow the properties of a linear droplet chain. For larger kick velocities, however, droplets may coalesce and separate again, showing distinct deviations from classicality. In the supersolid regime the normal modes are eliminated by a counterflow of mass between the droplets, signaled by a reduction of the center-of-mass motion. Our study effectively captures the vibrational patterns of isolated droplets in the presence of three-body loss and can be generalized to systems with a larger number of droplet arrays.