Eur. Phys. J. B (2012) 85: 168
https://doi.org/10.1140/epjb/e2012-21050-3

Regular Article

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

¹ Department of Physics, Tianjin Polytechnic University, Tianjin 300160, P.R. China
² College of Physical Sciences, Graduate University of Chinese Academy of Sciences, P.O. Box 4588, Beijing 100049, P.R. China
³ School of Physical Science and Technology, Soochow University, Suzhou, Jiangsu 215006, P.R. China

^a e-mail: ghliu@pku.edu.cn

Received: 19 December 2011
Received in final form: 26 February 2012
Published online: 28 May 2012

Abstract

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.