Quantum Correlations in Optical Angle–Orbital Angular Momentum Variables

Jonathan Leach, Barry Jack, J. Romero, Anand Kumar Jha, Alison M Yao, Sonja Franke-Arnold, David G. Ireland, Robert W. Boyd, Stephen M. Barnett, and Miles J. Padgett. Science 129, pp. 662 -- Select -  (2010).

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