非均匀磁场对XY模型三量子比特热纠缠度的影响The Thermal Entanglement Effects of Heisenberg XY Model Under Non-uniform Magnetic Field
张德华,陈宇光,张军
摘要(Abstract)：
利用海森堡XY模型,通过密度矩阵的方法研究了三量子比特在外加磁场下的热纠缠,计算了纠缠的度量——并协度,给出了有限温度条件下不同外加磁场下的纠缠行为.在此基础上,可以通过对外加磁场的调节对量子比特进行有效的控制,实现量子计算和得到最有利的纠缠.
关键词(KeyWords)： 量子信息;热纠缠;密度矩阵;非均匀磁场;并协度
基金项目(Foundation):
作者(Author): 张德华,陈宇光,张军
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参考文献(References)：
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