Thermal entanglement in a spin-1/2 Ising-Heisenberg butterfly-shaped chain with impurities  

作　　者：Meng-Ru Ma Yi-Dan Zheng Zhu Mao Bin Zhou 马梦如;郑一丹;毛竹;周斌(Department of Physics,Hubei University,Wuhan 430062,China)

机构地区：[1]Department of Physics,Hubei University,Wuhan 430062,China

出　　处：《Chinese Physics B》2020年第11期212-218,共7页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant No.12074101);the Science Fund for the New Century Excellent Talents in University of the Ministry of Education of China(Grant No.NCET-11-0960);the Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No.20134208110001).

摘　　要：We investigate the effect of impurities on the thermal entanglement in a spin-1/2 Ising-Heisenberg butterfly-shaped chain,where four interstitial Heisenberg spins are localized on the vertices of a rectangular plaquette in a unit block.By using the transfer-matrix approach,we numerically calculate the partition function and the reduced density matrix of this model.The bipartite thermal entanglement between different Heisenberg spin pairs is quantified by the concurrence.We also discuss the fluctuations caused by the impurities through the uniform distribution and the Gaussian distribution.Considering the effects of the external magnetic field,temperature,Heisenberg and Ising interactions as well as the parameter of anisotropy on the thermal entanglement,our results show that comparing with the case of the clean model,in both the twoimpurity model and the impurity fluctuation model the entanglement is more robust within a certain range of anisotropic parameters and the region of the magnetic field where the entanglement occurred is also larger.

关 键 词：thermal entanglement Ising–Heisenberg butterfly-shaped chain IMPURITIES transfer-matrix approach 

分 类 号：O413[理学—理论物理] TN918.1[理学—物理]