Effects of Heisenberg perturbation on the ground-state properties of one-dimensional extended quantum compass model

The ground-state properties and quantum phase transitions (QPTs) of the one-dimensional extended quantum compass model (EQCM) with Heisenberg perturbation are investigated by the infinite time-evolving block decimation (iTEBD) algorithm. The ground-state properties are found to be affected distinctively by the Heisenberg perturbation and rich phase diagrams are obtained. The first-order QPTs line at J1=0 disappears even with an infinitesimal Heisenberg perturbation and two interesting intermediate phases, such as a disordered phase and a transverse Néel phase, are induced. Both bipartite entanglement and fidelity per site are capable of describing all the second-order QPTs.