原子系综在二次方相互作用演化下多体纠缠特性

Multi-body entanglement characteristics of atomic ensemble under quadratic interaction evolution

利用平均量子Fisher信息度量了在二次方相互作用下体系的相互纠缠的特性,同时也考虑了加上线性相互作用项后体系多体纠缠演化的特点,结果表明在线性和非线性共同作用下自旋体系的多体纠缠保持的时间更久。考虑了体系在噪声影响下的纠缠产生过程,发现即便是有噪声的情况下,原子体系也还具有很高的纠缠度。这对于量子多体纠缠在量子精密测量和量子通信中的应用都有着极其重要的作用。

In this paper, the average quantum Fisher information was used to measure the entanglement characteristics of the system under the quadratic interaction. In addition, we considered the characteristics of the multi-body entanglement evolution of the system after adding the linear interaction term. The results showed that the multi-body entanglement of the spin system remains longer under the combined action of linear and nonlinear interactions. Moreover, we considered the entanglement process of the system under the influence of noise and found that the atomic system has a high degree of entanglement even in the presence of noise. This is extremely important for the application of quantum multi-body entanglement in quantum precision measurements and quantum communications.