外磁场下Dzyaloshinskii-Moriya相互作用对海森堡XYZ链热纠缠的影响

Effect of Dzyaloshinskii-Moriya Interaction on Thermal Entanglement of Heisenberg XYZ Chains Under External Magnetic Field

通过计算共生纠缠度,在外磁场存在的情况下研究了含有z方向Dzyaloshinskii-Moriya(DM)相互作用的两量子比特海森堡XYZ链模型的热纠缠特性。研究结果显示:对于反铁磁情形下的海森堡XYZ链模型,随着DM相互作用参数|D|的增加,原本没有热纠缠的自旋链发生热纠缠;并且随着DM相互作用的增强,自旋链的热纠缠逐渐趋于稳定,自旋链的最大纠缠度也有所提高;随着自旋耦合参数Jz的逐渐增加,自旋链的最大纠缠度增加,热纠缠范围得到扩展;各向异性参数γb的增加有助于扩展热纠缠的范围,但对自旋链的最大纠缠度无明显的影响。

The thermal entanglement characteristics in the two-qubit Heisenberg XYZ chain model under the Dzyaloshinskii-Moriya(DM) interaction along the z direction is studied by the calculation of the symbiotic entanglement in the presence of an external magnetic field. The research results show that as for the Heisenberg XYZ chain model in the antiferromagnetic case,with the increase of the DM interaction parameter| D |,the spin chain without original thermal entanglement becomes thermally entangled. Meanwhile,as the DM interaction increases,the thermal entanglement of the spin chain gradually tends to be stable and the maximum entanglement degree of the spin chain also increases. With the gradual increase of the spin coupling parameter Jz,the maximum entanglement degree of the spin chain increases and the range of thermal entanglement is extended. The increase of the anisotropy parameter γbhelps to expand the range of thermal entanglement,but it has no obvious effect on the maximum entanglement degree of spin chains.