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arXiv · 1204.1293

Imaging high-dimensional spatial entanglement with a camera

Matthew P. Edgar·Daniel S. Tasca·Frauke Izdebski·Ryan E. Warburton·Jonathan Leach·Megan Agnew·Gerald S. Buller·Robert W. Boyd·Miles J. Padgett
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Abstract

The light produced by parametric down-conversion shows strong spatial entanglement that leads to violations of EPR criteria for separability. Historically, such studies have been performed by scanning a single-element, single-photon detector across a detection plane. Here we show that modern electron-multiplying charge-coupled device cameras can measure correlations in both position and momentum across a multi-pixel field of view. This capability allows us to observe entanglement of around 2,500 spatial states and demonstrate Einstein-Podolsky-Rosen type correlations by more than two orders of magnitude. More generally, our work shows that cameras can lead to important new capabilities in quantum optics and quantum information science.

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Matthew P. Edgar, Daniel S. Tasca, Frauke Izdebski, Ryan E. Warburton, Jonathan Leach, Megan Agnew, Gerald S. Buller, Robert W. Boyd, Miles J. Padgett. 2012-04-05. Imaging high-dimensional spatial entanglement with a camera. https://doi.org/10.1038/ncomms1988

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