Bipartite entanglement of the one-dimensional extended quantum compass model in a transverse field

By using the infinite time-evolving block decimation (iTEBD) method, we obtain the ground state wave function of the one-dimensional quantum compass model in a transverse field in the form of a matrix product state (MPS). Based on the MPS, quantum entanglement, order parameters, and correlation functions are calculated numerically. The bipartite entanglement measure which is defined by the singular values obtained from the singular value decomposition (SVD) of tensors is found to be capable of detecting all the quantum phase transitions in this model. The rich phase diagram that we have obtained supports that suggested previously by using the Jordan-Wigner transformation. In addition, some order parameters used to characterise different phases are also introduced.