Entanglement witnesses and measures for bright squeezed vacuum
Entanglement witnesses and measures for bright squeezed vacuum
复制标题
光亮压缩真空的纠缠见证和措施
DOI：
10.1103/physreva.86.022323
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发表时间：
2012
影响因子：
2.9
通讯作者：
M. Chekhova
中科院分区：
文献类型：
--
作者：
M. Stobi'nska;F. Toppel;P. Sekatski;M. Chekhova
量子纠缠是一个令人着迷的现象，特别是如果它是在宏观尺度上观察的话。重要的是，只有通过准确的测量结果和策略才能揭示宏观量子关联。在这里，我们以宏观布居的偏振三重态Bell态的形式来描述明亮压缩真空的可行纠缠见证。他们的测试包括有效的光探测和斯托克斯算符方差的测量。我们还计算了这些态的纠缠度量，如施密特数和对数负性。结果表明，偏振纠缠的明亮压缩真空度与平均光子数的平方成正比。我们分析了施密特数的运算模拟的适用性。
Quantum entanglement is a fascinating phenomenon, especially if it is observed at the macroscopic scale. Importantly, macroscopic quantum correlations can be revealed only by accurate measurement outcomes and strategies. Here, we formulate feasible entanglement witnesses for bright squeezed vacuum in the form of the macroscopically populated polarization triplet Bell states. Their testing involves efficient photodetection and the measurement of the Stokes operators' variances. We also calculate the measures of entanglement for these states such as the Schmidt number and the logarithmic negativity. Our results show that the bright squeezed vacuum degree of polarization entanglement scales as the mean photon number squared. We analyze the applicability of an operational analog of the Schmidt number.