Imaging high-dimensional spatial entanglement with a camera

• DOI: 10.1038/ncomms1988
• Publication Date: 2012-08-07T09:44:58Z
• Authors: M.P. Edgar; D.S. Tasca; F. Izdebski; R.E. Warburton; J. Leach; M. Agnew; G.S. Buller; R.W. Boyd; M.J. Padgett
• Keywords: Quantum Physics; 0103 physical sciences; FOS: Physical sciences; Quantum Physics (quant-ph); 01 natural sciences; Article; Physics - Optics; Optics (physics.optics)

5 pages, 4 figures<br/>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.<br/>