Matter-wave dromions in a disk-shaped dipolar Bose-Einstein condensate with the Lee-Huang-Yang correction

We investigate, both analytically and numerically, the nonlinear dynamics of (2+1)-dimensional [(2+1)D] matter waves excited in a disk-shaped dipolar Bose-Einstein condensate (BEC) when quantum fluctuations described by the Lee-Huang-Yang (LHY) correction are taken into consideration. By using a method of multiple scales, we derive Davey-Stewartson I equations that govern the nonlinear evolution of matter-wave envelopes. We demonstrate that the system supports (2+1)D matter-wave dromions, which are superpositions of a short-wavelength excitation and a long-wavelength mean flow. We found that the stability of the matter-wave dromions can be enhanced by the LHY correction. We also found that such dromions display interesting behaviors of collision, reflection, and transmission when they interact with each other and are scattered by obstacles. The results reported here are useful not only for improving the understanding on the physical property of the quantum fluctuations in BECs, but also for possible experimental findings of new nonlinear localized excitations in systems with long-ranged interactions.