Topological flat bands in dipolar spins

Topological Flat Bands from Dipolar Spin Systems
N.Y. Yao, C. R. Laumann, A.V. Gorshkov, S. D. Bennett, E. Demler, P. Zoller, and M. D. Lukin
Phys. Rev. Lett. 109, 266804 (2012)

Schematic representation of a 2D dipolar droplet. The grey droplet represents a 2D array of interacting tilted dipoles. The dipoles are tilted by a static field in the ^z direction, oriented at 0, 0 relative to the lattice basis fX; Y; Zg.Rij is a vector connecting dipoles in the XY plane.