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Testing foundations of quantum mechanics with photons

Nature Physics volume 10, pages 278–286 (2014)Cite this article

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Abstract

Quantum mechanics continues to predict effects at odds with a classical understanding of nature. Experiments with light at the single-photon level have historically been at the forefront of fundamental tests of quantum theory and the current developments in photonic technologies enable the exploration of new directions. Here we review recent photonic experiments to test two important themes in quantum mechanics: wave–particle duality, which is central to complementarity and delayed-choice experiments; and Bell nonlocality, where the latest theoretical and technological advances have allowed all controversial loopholes to be separately addressed in different experiments.

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Figure 1: Delayed-choice experimental set-ups.
Figure 2: A nonlocality experiment and associated loopholes.
Figure 3: Experiments for closing the Bell nonlocality loopholes.
Figure 4: EPR steering.

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Acknowledgements

We are grateful for financial support from EPSRC, ERC, NSQI (S.G.). J.C.F.M. is supported by a Leverhulme Trust Early-Career Fellowship. J.L.O.B. acknowledges a Royal Society Wolfson Merit Award and a Royal Academy of Engineering Chair in Emerging Technologies. We thank P. Birchall, N. Brunner and C. Sparrow for helpful comments.

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  1. H. H. Wills Physics Laboratory and Department of Electrical and Electronic Engineering, Centre for Quantum Photonics, University of Bristol, Merchant Venturers Building, Woodland Road, Bristol, BS8 1UB, UK

    Peter Shadbolt, Jonathan C. F. Mathews, Anthony Laing & Jeremy L. O'Brien

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Shadbolt, P., Mathews, J., Laing, A. et al. Testing foundations of quantum mechanics with photons. Nature Phys 10, 278–286 (2014). https://doi.org/10.1038/nphys2931

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