摘要
采用生成函数和纠缠交换的方法,研究了混态情况下量子小世界网络的纠缠渗流.基于理论计算及数值模拟,分析了小世界网络归一化平均集团的大小和路径长度的关系.结果表明小世界网络在较短的路径下具有较大的平均集团.进一步阐明了量子小世界网络具有较大的聚类特性和较短的平均距离,发现平均集团随着保真度的增加而增大,且增大小世界网络的平均度可以降低信息传递所需的保真度.通过对混态进行纠缠交换.可提高最大纠缠态的保真度,说明纠缠交换可以优化量子小世界网络的纠缠渗流.
Entanglement percolation of quantum small-world networks in mixed state is investigated by means of generating function and entanglement swapping method. Based on theoretical calculation and numerical simulation, the relationship between normalized average component size and path length in smallworld networks is analyzed. Results show that the small world networks have a larger average component size under the shorter paths in small-world network. It is further demonstrated that quantum small-world networks have larger aggregation and shorter average paths. It is found that the average component size increases with the increase of fidelity, and increasing the average degree of small-world networks can reduce the fidelity required for information delivery. The fidelity of maximum entangled states can be improved by entanglement swapping of mixed states, which shows that entanglement swapping can optimize the entanglement percolation in quantum small-world networks.
引文
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