Exploring the Quantum Nature of the Radial Degree of Freedom of a Photon via Hong-Ou-Mandel Interference

E. Karimi, D. Giovannini, E. Bolduc, N. Bent, F. M. Miatto, M. J. Padgett, and R. W. Boyd, Phys. Rev. A 89, 013829 (2014).

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