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arXiv · 2006.09496

Testing higher-order quantum interference with many-particle states

Marc-Oliver Pleinert·Alfredo Rueda·Eric Lutz·Joachim von Zanthier
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Abstract

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 bounded 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.

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Marc-Oliver Pleinert, Alfredo Rueda, Eric Lutz, Joachim von Zanthier. 2021-05-12. Testing higher-order quantum interference with many-particle states. https://doi.org/10.1103/physrevlett.126.190401

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