不同方向非均匀磁场对Heisenberg XYZ 链中热纠缠的影响

采用纠缠度量方法Negativity研究了包含不同方向非均匀磁场自旋为1的两粒子Heisenberg XYZ 链的量子纠缠特性。研究发现，系统处于基态时有量子相变发生，铁磁和反铁磁情形下纠缠的表现行为完全不同，故可以利用这种性质来生成所需纠缠。研究还发现纠缠伴随非均匀磁场的变化有震荡现象，并且x方向和y方向的纠缠存在先消失后复苏现象。纠缠随系统其他参数的变化会因磁场方向的不同而有完全不一样的特征，从而可以通过调节磁场方向、各向异性参数等来提高纠缠值和扩大纠缠范围。

Effect of different inhomogeneous magnetic fields on thermal entanglement in a two-qutrit Heisenberg XYZ chain

The quantum entanglement of two-qutrit Heisenberg XYZ chains interacting with different inhomogeneous magnetic fields is investigated by means of negativity. It is found that the quantum phase transition occurs when the system is in the ground state. The behaviors of entanglement in ferromagnetic and anti-ferromagnetic are totally different. So, entanglement can be produced by this feature. It’s also found that the entanglement behaves oscillator when the external magnetic field becomes inhomogeneous. And the x and y component magnetic fields can induce the entanglement to disappear and then to revive. The dependence of the entanglement on parameters varies with different magnetic fields. The entanglement can be controlled by adjusting the directions of external magnetic field and the anisotropy couplings Jz.