Extended Bose-Hubbard model with dipolar and contact interactions

Abstract

We study the phase diagram of the one-dimensional boson gas trapped inside an optical lattice with contact and dipolar interaction, taking into account next-nearest terms for both tunneling and interaction. Using the density-matrix renormalization group, we calculate how the locations of phase transitions change with increasing dipolar interaction strength for average density $\ensuremath{\rho}=1$. Furthermore, we show the emergence of pair-correlated phases for a large dipolar interaction strength and $\ensuremath{\rho}\ensuremath{\ge}2$, including a supersolid phase with an incommensurate density wave ordering manifesting the corresponding spontaneous breaking of the translational symmetry.