含三体相互作用的海森堡自旋链纠缠研究

Entanglement in a Three-spin Interaction Heisenberg Spin Chain

研究了含三体相互作用的海森堡自旋链的能级和相应本征态的纠缠情况,详细分析了含有三个粒子的海森堡自旋链的纠缠,发现所有的纠缠态都为W态。给出三粒子海森堡自旋链在温度为零时的基态纠缠,发现反铁磁自旋链的基态不随各向异性、耦合强度等参数发生变化,铁磁自旋链的基态纠缠随各向异性因子和三自旋耦合项而改变。讨论了三比特自旋链在低温时的热纠缠,给出纠缠度表达式及其随温度、各向异性因子和耦合强度的变化关系。

The energy level and the eigenstate entanglement in a Heisenberg spin chain with three-spin interaction are analysed. We study the entanglement in a tri-qubit Heisenberg spin chain, the entangled states are all W state. And the ground state entanglement are analysed when the temperature is zero. We find that the entanglement in the antiferromagnetic chain doesnt t change with the parameters. The entanglement in the ferromagnetic chain changes with the anisotropy and three-spin interaction. We also study the thermal entanglement in the system under low temperature. The function of the entanglement is expressed and the relation with temperature, anisotropy and interaction are pictured.