https://doi.org/10.1140/epjb/e2015-60391-y
Regular Article
Dimerized phase and entanglement in the one-dimensional spin-1 bilinear biquadratic model
1
Department of Applied Physics, Xi’an Jiaotong
University, Xi’an
710049, P.R. China
2
School of Science, Xi’an Polytechnic University,
Xi’an 710048, P.R.
China
3
Laboratory of Forensic Medicine and Biomedical Information,
Chongqing Medical University, Chongqing
400016, P.R.
China
a
e-mail: chenaiminxa@163.com
Received: 17 May 2015
Received in final form: 29 July 2015
Published online: 21 October 2015
Dimerized phase and quantum entanglement are investigated in the one-dimensional spin-1 bilinear biquadratic model. Employing the infinite matrix product state representation, groundstate wavefunctions are numerically obtained by using the infinite time evolving block decimation method in the infinite lattice system. From a bipartite entanglement measure of the groundstates, i.e., von Neumann entropy, the phase transition points can be clearly extracted. Moreover, the even-bond and odd-bond von Neumann entropies show two different values in the spontaneous dimerized phase. It implies that the quantum entanglement can distinguish the two degenerate groundstates. Then, we define a dimer entropy in the spontaneous dimerized phase. Comparing to the dimer order parameter, the dimer entropy can play a role of a local order parameter to characterize the spontaneous dimerized phase.
Key words: Solid State and Materials
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2015