Realizing the strongly correlated d-wave Mott-insulator state in a fermionic cold-atom optical lattice

We show that a new state of matter, the d-wave Mott-insulator state (d-Mott state) (introduced recently by), which is characterized by a nonzero expectation value of a local plaquette operator embedded in an insulating state, can be engineered using ultracold atomic fermions in two-dimensional double-well optical lattices. We characterize and analyze the parameter regime where the d-Mott state is stable. We predict the testable signatures of the state in the time-of-flight measurements.