多量子位Heisenberg模型中纠缠的时间演化特性

研究了多量子位Heisenberg模型中纠缠的时间演化特性, 并给出了平均纠缠度〈C〉和多体纠缠度Q的解析表达式. 结果发现无论是对〈C〉还是对Q随着时间t的不断增长, 它们均先线性的增大, 而后达到一近似稳定状态, 并绕一平衡值做无规则的上下震荡. 若进一步考察N〈C〉则还可以发现, 纠缠上下震荡的平衡值与Heisenberg链的长度几乎无关, 而仅由它们的次近邻耦合常数J决定.

Dynamics of Multipartite Entanglement in the Heisenberg Model

We investigate dynamics of the multipartite entanglement in the Heisenberg model and give analytical expressions of the average concurrence and the multipartite entanglement measure Q. It is found that both and Q initially increase with the increase of the scaled time t, and finally reach a plateau, oscillating irregularly around a steady value. And for the case of N, this steady value is nearly independent of the length of the chain, and only determined by the NNN coupling constant J.