标题： 量子离散度和广义n-qubit维尔纳态中的对数 negativity 显示英文标题

标题： Quantum Discord and Logarithmic Negativity in the Generalized n-qubit Werner State

摘要： 量子 discord (QD) 是衡量量子系统总量子非局域关联的一种度量。 量子 discord 的形式已被应用于各种两量子比特混合态，并且已有报告指出，即使在这些状态未纠缠时，也会存在非零的量子 discord。 为此，我们计算了高于两个量子比特的混合态的量子 discord，即具有双部分分裂的一般 n 量子比特 Werners 态。 我们发现，在热力学极限下，QD 饱和为一条斜率为 1 的直线。 使用对数负值对两个子系统之间的纠缠进行定性研究显示，它们之间的纠缠内容随着量子比特数量的增加而非均匀地增加，最终达到饱和。 我们已通过解析方法和数值方法证明了上述论断。 显示英文摘要

摘要： Quantum Discord (QD) is a measure of the total quantum non-local correlations of a quantum system. The formalism of quantum discord has been applied to various two-qubit mixed states and it has been reported that there is a non-zero quantum discord even when the states are unentangled. To this end, we have calculated the Quantum Discord for higher than two qubit mixed state, that is, the generalized n-qubit Werner state with a bipartite split. We found that the QD saturates to a straight line with unit slope in the thermodynamic limit. Qualitative studies of entanglement between the two subsystems using logarithmic negativity revealed that the entanglement content between them increases non-uniformly with the number of qubits leading to its saturation. We have proved the above claims both analytically and numerically.