Dipolar Fermions in Quasi-Two-Dimensional Square Lattice

Mehrtash Babadi, Eugene Demler

Theja N. De Silva

Georg M. Bruun

Anne-Louise Gadsbølle, Georg M. Bruun

We consider dipolar fermions in a two-dimensional square lattice and a harmonic trapping potential. The anisotropy of the dipolar interaction combined with the lattice leads to transitions between phases with density order of different symmetries. We show that the attractive part of the dipolar interaction results in a superfluid phase that is suppressed by density order. The trapping potential is demonstrated to make the different phases coexist, forming ring and island structures. The phases with density and superfluid order can overlap, forming regions with supersolid order.

Sadhan K. Adhikari

We study the formation of solitons in a uniform quasi-two-dimensional (quasi-2D) spin-orbit (SO) coupled self-repulsive binary dipolar and nondipolar Bose-Einstein condensate (BEC) using the mean-field Gross-Pitaevskii equation. For a weak SO coupling, in a nondipolar BEC, one can have three types of degenerate solitons: a multiring soliton with intrinsic vorticity of angular momentum projection +1 or -1 in one component and 0 in the other, a circularly asymmetric soliton, and a stripe soliton with stripes in the density. For an intermediate SO coupling, the multiring soliton ceases to exist and a square-lattice soliton appears with a spatially periodic pattern in density on a square lattice, in addition to the degenerate circularly asymmetric and stripe solitons. In the presence of a dipolar interaction, with the polarization direction aligned in the quasi-2D plane, only the degenerate circularly asymmetric and stripe solitons appear.

Nikolaj Thomas Zinner, Bernard Wunsch, David Pekker +1 more