Pairwise thermal entanglement in a three-qubit Heisenberg XX model with a nonuniform magnetic field and Dzyaloshinski-Moriya interaction

作     者：任金忠 邵晓强 张寿 Yeon Kyu-Hwang 

作者机构：Department of Physics College of Science Yanbian University Center for the Condensed-Matter Science and Technology Department of Physics Harbin Institute of Technology BK21 Program Physics and Department of Physics College of Natural Science Chungbuk National University 

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

年 卷 期：2010年第19卷第10期

页      面：74-80页

核心收录：

学科分类：070207[理学-光学] 07[理学] 08[工学] 0803[工学-光学工程] 0702[理学-物理学] 

主　　题：thermal entanglement nonuniform magnetic field Dzyaloshinski-Moriya interaction,Heisenberg model 

摘      要：Pairwise thermal entanglement in a three-qubit Heisenberg XX model is investigated when a nonuniform mag- netic field and the Dzyaloshinski-Moriya interaction are included. We find that the nonuniform magnetic field and Dzyaloshinski-Moriya interaction are the more efficient control parameters for the increase of entanglement and critical temperature. For both the nearest neighbour sites and the next nearest neighbour sites, the magnetic field can induce entanglement to a certain extent and the Dzyaloshinski-Moriya interaction can enhance the entanglement to a stable value. The steady value of the nearest neighbour site entanglement C12 is larger than the next nearest neighbour site entanglement C13. An interesting phenomenon is that the entanglement curve of C12 appears a peak value when the Dzyaloshinski-Moriya interaction is considered in a nonuniform magnetic field.