Charge ordering and hopping in a triangular array of quantum dots

We demonstrate a mapping between the problem of charge ordering in a triangular array of quantum dots and a frustrated Ising spin model. Charge correlation in the low temperature state is characterized by an intrinsic height field order parameter. Different ground states are possible in the system, with a rich phase diagram. We show that electronic hopping transport is sensitive to the properties of the ground state, and describe the singularities of hopping conductivity at the freezing into an ordered state.