Sperling J, Bohmann M, Vogel W, Harder G, Brecht B, Ansari V, Silberhorn C
Arbeitsgruppe Theoretische Quantenoptik, Institut für Physik, Universität Rostock, D-18051 Rostock, Germany.
Integrated Quantum Optics Group, Applied Physics, University of Paderborn, 33098 Paderborn, Germany.
Phys Rev Lett. 2015 Jul 10;115(2):023601. doi: 10.1103/PhysRevLett.115.023601. Epub 2015 Jul 7.
We report on the implementation of a time-multiplexed click detection scheme to probe quantum correlations between different spatial optical modes. We demonstrate that such measurement setups can uncover nonclassical correlations in multimode light fields even if the single mode reductions are purely classical. The nonclassical character of correlated photon pairs, generated by a parametric down-conversion, is immediately measurable employing the theory of click counting instead of low-intensity approximations with photoelectric detection models. The analysis is based on second- and higher-order moments, which are directly retrieved from the measured click statistics, for relatively high mean photon numbers. No data postprocessing is required to demonstrate the effects of interest with high significance, despite low efficiencies and experimental imperfections. Our approach shows that such novel detection schemes are a reliable and robust way to characterize quantum-correlated light fields for practical applications in quantum communications.
我们报告了一种时间复用点击检测方案的实施情况,以探测不同空间光学模式之间的量子关联。我们证明,即使单模约化是纯经典的,这种测量设置也能揭示多模光场中的非经典关联。利用点击计数理论,而不是采用光电检测模型的低强度近似,由参量下转换产生的关联光子对的非经典特性可立即测量。该分析基于二阶及更高阶矩,对于相对较高的平均光子数,这些矩可直接从测量的点击统计中获取。尽管效率较低且存在实验缺陷,但无需数据后处理就能以高显著性证明感兴趣的效应。我们的方法表明,这种新颖的检测方案是在量子通信实际应用中表征量子关联光场的可靠且稳健的方式。