Atomic quantum simulator for lattice gauge theories and ring exchange   models
  We present the design of a ring exchange interaction in cold atomic gases subjected to an optical lattice using well understood tools for manipulating and controlling such gases. The strength of this interaction can be tuned independently and describes the correlated hopping of two bosons. We discuss a setup where this coupling term may allows for the realization and observation of exotic quantum phases, including a deconfined insulator described by the Coulomb phase of a three-dimensional U(1) lattice gauge theory. 
H.P. B\"uchler, M. Hermele, S.D. Huber, Matthew P.A. Fisher, and P.   Zoller