Pleinert Marc-Oliver, Rueda Alfredo, Lutz Eric, von Zanthier Joachim
Institut für Optik, Information und Photonik, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91058 Erlangen, Germany.
Erlangen Graduate School in Advanced Optical Technologies (SAOT), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91052 Erlangen, Germany.
Phys Rev Lett. 2021 May 14;126(19):190401. doi: 10.1103/PhysRevLett.126.190401.
Quantum theory permits interference between indistinguishable paths but, at the same time, restricts its order. Single-particle interference, for instance, is limited to the second order, that is, to pairs of single-particle paths. To date, all experimental efforts to search for higher-order interferences beyond those compatible with quantum mechanics have been based on such single-particle schemes. However, quantum physics is not bound to single-particle interference. We here experimentally study many-particle higher-order interference using a two-photon-five-slit setup. We observe nonzero two-particle interference up to fourth order, corresponding to the interference of two distinct two-particle paths. We further show that fifth-order interference is restricted to 10^{-3} in the intensity-correlation regime and to 10^{-2} in the photon-correlation regime, thus providing novel bounds on higher-order quantum interference.
量子理论允许不可区分路径之间的干涉，但同时也限制了其阶数。例如，单粒子干涉限于二阶，即限于单粒子路径对。迄今为止，所有寻找超出与量子力学兼容范围的高阶干涉的实验努力都是基于此类单粒子方案。然而，量子物理并不局限于单粒子干涉。我们在此使用双光子五缝装置对多粒子高阶干涉进行了实验研究。我们观察到了高达四阶的非零双粒子干涉，这对应于两条不同双粒子路径的干涉。我们进一步表明，在强度关联 regime 中，五阶干涉被限制在 10^{-3}，在光子关联 regime 中被限制在 10^{-2}，从而为高阶量子干涉提供了新的界限。
