Strong to weak interacting-topological phase transition of bosons on a lattice

Abstract

We study hard-core bosons on the honeycomb lattice subjected to anisotropic nearest-neighbor hopping along with anisotropic nearest-neighbor repulsion, using a quantum Monte Carlo technique. At half-filling, we find a transition from strong interacting-topological order to weak interacting-topological order as function of the hopping anisotropy. The strong topological phase is characterized by a finite topological entanglement entropy, while the weak topological order is identified with a non-trivial value of the bipartite entanglement entropy. Some of the order parameters and their derivatives demonstrate abrupt changes when varying the parameters controlling the lattice anistropies, thus revealing the nature of this interacting-topological phase transition.