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arXiv · 1308.2554

Quantum walks of correlated photon pairs in two-dimensional waveguide arrays

Konstantinos Poulios·Robert Keil·Daniel Fry·Jasmin D. A. Meinecke·Jonathan C. F. Matthews·Alberto Politi·Mirko Lobino·Markus Gräfe·Matthias Heinrich·Stefan Nolte·Alexander Szameit·Jeremy L. O'Brien
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Abstract

We demonstrate quantum walks of correlated photons in a 2D network of directly laser written waveguides coupled in a 'swiss cross' arrangement. The correlated detection events show high-visibility quantum interference and unique composite behaviour: strong correlation and independence of the quantum walkers, between and within the planes of the cross. Violations of a classically defined inequality, for photons injected in the same plane and in orthogonal planes, reveal non-classical behaviour in a non-planar structure.

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Konstantinos Poulios, Robert Keil, Daniel Fry, Jasmin D. A. Meinecke, Jonathan C. F. Matthews, Alberto Politi, Mirko Lobino, Markus Gräfe, Matthias Heinrich, Stefan Nolte, Alexander Szameit, Jeremy L. O'Brien. 2013-08-12. Quantum walks of correlated photon pairs in two-dimensional waveguide arrays. https://doi.org/10.1103/physrevlett.112.143604

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