Ultracold dipolar bosons trapped in atomtronic circuits

We consider a ring-shaped triple-well potential with few polar bosons characterized by a long-range and anisotropic interaction. By diagonalizing the extended Bose-Hubbard Hamiltonian, that treats sites as macroscopic dipoles, we investigate the ground state properties of the system as we rotate the dipole angle and vary the on-site interaction strength. We find that the competition between dipole and on-site interaction lead to different ground states and that the entanglement between sites depends on the filling factor which can be fractional or integer, and whether the number of particles is odd or even. We further characterize the system by studying the condensed fraction and coherence properties.