海森伯格XXZ模型在不均匀磁场下的负值度

摘要

The thermal entanglement of the two-qubit anisotropic Heisenberg XXZ model under an inhomogeneous magnetic field by means of Negativity is studied.The thermal entanglement and the critical temperature increase when the coupling coefficient Jz increases.The critical magnetic field increases with increasing the inhomogeneous magnetic field b but the maximum entanglement value of the system becomes smaller.The Negativity decreases with increasing.%利用负值度（Negativity）研究了两量子比特各向异性海森伯格XXZ模型在外加不均匀磁场下的热纠缠.耦合系数越大,系统的纠缠度越大,临界温度越高.磁场越大,临界磁场越高,但系统的最大纠缠度却降低,且负值度随的绝对值的增大而减小.