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arXiv · 2102.11562

Modified quantum delayed-choice experiment without quantum control

Qi Guo·Wen-Jie Zhang·Gang Li·Tiancai Zhang·Hong-Fu Wang·Shou Zhang
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Abstract

Wheeler's delayed-choice experiment delays the decision to observe either the wave or particle behavior of a photon until after it has entered the interferometer, and the quantum delayed-choice experiment provides the possibility of observing the wave and particle behavior simultaneously by introducing quantum control device. We here propose a modified quantum delayed-choice experiment without quantum control or entanglement assistance, in which a photon can be prepared in a wave-particle superposition state and the morphing behavior of wave-to-particle transition can be observed easily. It is demonstrated that the presented scheme can allow us to rule out classical hidden variable models in a device-independent manner via violating dimension witness. We also extend the scheme to the situation of two degrees of freedom, first constructing a hybrid quantum delayed-choice experiment which enables simultaneous observation of a photon's wave and particle behaviors in different degrees of freedom, and then proposing a scheme to prepare the single-photon wave-particle entanglement. This study is not only meaningful to explore the wave and particle properties of photons, but also provides potential for the research of the single-particle nonlocality from the perspective of the wave-particle degree of freedom.

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Qi Guo, Wen-Jie Zhang, Gang Li, Tiancai Zhang, Hong-Fu Wang, Shou Zhang. 2021-02-23. Modified quantum delayed-choice experiment without quantum control. https://doi.org/10.1103/physreva.104.022210

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