Bipartite entanglement in spin-1/2 Heisenberg model

作     者：胡明亮 田东平 

作者机构：Department of Applied Mathematics and Applied PhysicsXi'an Institute of Posts and Telecommunications 

出 版 物：《Chinese Physics C》 (中国物理C（英文版）)

年 卷 期：2008年第32卷第4期

页      面：303-307页

核心收录：

学科分类：0709[理学-地质学] 08[工学] 0708[理学-地球物理学] 0804[工学-仪器科学与技术] 0827[工学-核科学与技术] 0703[理学-化学] 0704[理学-天文学] 0702[理学-物理学] 081202[工学-计算机软件与理论] 0812[工学-计算机科学与技术（可授工学、理学学位）] 

基　　金：National Natural Science Foundation of China(10547008) 

主　　题：Heisenberg model bipartite entanglement negativity 

摘      要：The bipartite entanglement of the two- and three-spin Heisenberg model was investigated by using the concept of negativity. It is found that for the ground-state entanglement of the two-spin model, the negativity always decreases as B increases if △ 〈γ- 1, and it may keep a steady value of 0.5 in the region of B 〈 J[（△＋ 1）2 -γ^2]^1/2 if △ 〉γ-1, while for that of the three-spin model, the negativity exhibits square wave structures if γ=0 or△=0. For thermal states, there are two areas showing entanglement, namely, the main region and the sub-region. The main region exists only when △ 〉 △c （△c =γ- 1 and （γ^2 - 1）/2 for the 2- and 3-spin model respectively） and extends in terms of B and T as A increases, while the sub-region survives only when γ≠0 and shrinks in terms of B and T as △ increases.