Dynamic Stimulation of Phase Coherence in Lattice Bosons

The existence of superfluidity depends on the energy distribution of~excitations in a system. However, the distribution at thermal equilibrium is rarely optimal for the manifestation of long-range phase coherence. We show that by pushing a system of lattice bosons out of equilibrium with periodic driving, it is possible to increase or decrease the phase coherent region in the phase diagram of the Bose-Hubbard model.~We demonstrate this by calculating the non-equilibrium spatial correlation function~using a synthesis of Keldysh and Floquet theories. This work is supported by DARPA-MTO.