Realizing Fractional Chern Insulators with Dipolar Spins
  Strongly correlated quantum systems can exhibit exotic behavior controlled by topology. We predict that the \nu=1/2 fractional Chern insulator arises naturally in a two-dimensional array of driven, dipolar-interacting spins. As a specific implementation, we analyze how to prepare and detect synthetic gauge potentials for the rotational excitations of ultra-cold polar molecules trapped in a deep optical lattice. While the orbital motion of the molecules is pinned, at finite densities, the rotational excitations form a fractional Chern insulator. We present a detailed experimental blueprint for KRb, and demonstrate that the energetics are consistent with near-term capabilities. Prospects for the realization of such phases in solid-state dipolar systems are discussed as are their possible applications. 
Norman Y. Yao, Alexey V. Gorshkov, Chris R. Laumann, Andreas M.   L\"auchli, Jun Ye, Mikhail D. Lukin
cond-mat.str-el cond-mat.quant-gas quant-ph