中国物理B ›› 2007, Vol. 16 ›› Issue (8): 2229-2236.doi: 10.1088/1009-1963/16/8/013
朱燕, 朱士群, 郝翔
Zhu Yan(朱燕), Zhu Shi-Qun(朱士群)†, and Hao Xiang (郝翔)
摘要: The entanglement in an anisotropic spin-1 Heisenberg chain with a uniform magnetic field is investigated. The ground-state entanglement will undergo two different kinds of transitions when the anisotropy \Delta and the amplitude of the magnetic field B are varied. The thermal entanglement of the nearest neighbour always declines when B increases no matter what the value of the anisotropy is. It is very interesting to note that the entanglement of the next-nearest neighbour can increase to a maximum at a certain magnetic field. Regardless of the boundary condition, the nearest-neighbour entanglement always decreases and approaches to a constant value when the size of the system is very large. The constant value of open boundary condition is much larger than that of periodic boundary condition.
中图分类号: (Quantized spin models, including quantum spin frustration)