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arXiv · 1804.03494

Quantum metasurface for multi-photon interference and state reconstruction

Kai Wang·James G. Titchener·Sergey S. Kruk·Lei Xu·Hung-Pin Chung·Matthew Parry·Ivan I. Kravchenko·Yen-Hung Chen·Alexander S. Solntsev·Yuri S. Kivshar·Dragomir N. Neshev·Andrey A. Sukhorukov
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Abstract

Metasurfaces based on resonant nanophotonic structures have enabled novel types of flat-optics devices often outperforming the capabilities of bulk components, yet these advances remain largely unexplored for quantum applications. We show that non-classical multi-photon interferences can be achieved at the subwavelength scale in all-dielectric metasurfaces. We simultaneously image multiple projections of quantum states with a single metasurface, enabling a robust reconstruction of amplitude, phase, coherence, and entanglement of multi-photon polarization-encoded states. One- and two-photon states are reconstructed through nonlocal photon correlation measurements with polarization-insensitive click-detectors positioned after the metasurface, and the scalability to higher photon numbers is established theoretically. Our work illustrates the feasibility of ultra-thin quantum metadevices for the manipulation and measurement of multi-photon quantum states with applications in free-space quantum imaging and communications.

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Kai Wang, James G. Titchener, Sergey S. Kruk, Lei Xu, Hung-Pin Chung, Matthew Parry, Ivan I. Kravchenko, Yen-Hung Chen, Alexander S. Solntsev, Yuri S. Kivshar, Dragomir N. Neshev, Andrey A. Sukhorukov. 2018-04-10. Quantum metasurface for multi-photon interference and state reconstruction. https://doi.org/10.1126/science.aat8196

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