Entanglement in a spin-one spin chain

被引:21
作者
Zhang, GF
Li, SS
机构
[1] Chinese Acad Sci, Inst Semicond, State Key Lab Superlattices & Microstruct, Beijing 100083, Peoples R China
[2] CCAST, World Lab, China Ctr Adv Sci & Technol, Beijing 100080, Peoples R China
关键词
thermal entanglement; two-spin-qubit system; negativity;
D O I
10.1016/j.ssc.2006.01.040
中图分类号
O469 [凝聚态物理学];
学科分类号
070205 ;
摘要
The thermal entanglement in a two-spin-qutrit system with two spins coupled by exchange interaction is investigated in terms of the measure of entanglement called 'negativity'. We strictly show that for any temperature the entanglement is symmetric with respect to zero magnetic field. The behavior of negativity is presented for four different cases. We find that the entanglement may be enhanced under a nonuniform magnetic field. Because there is not any necessary and sufficient condition for quantum separability in systems of dimension 3 circle times 3, our results are qualitative, not quantitative. (c) 2006 Elsevier Ltd. All rights reserved.
引用
收藏
页码:17 / 21
页数:5
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