Phase transitions in an interacting boson model with near-neighbor repulsion

Abstract
We study the order of the zero temperature quantum phase transitions at density ρ=1 in the one-dimensional extended boson Hubbard model by examining the order parameter distribution and hysteresis effects. The phase diagram of the model at ρ=1/2, a generalization of the spin-1/2 XXZ Hamiltonian, is also obtained, and the possibility of a supersolid region is discussed.