Violation of local realism in a high-dimensional two-photon setup with non-integer spiral phase plates

Oemrawsingh, S. S. R.; Aiello, A.; Eliel, E. R.; Nienhuis, G.; Woerdman, J. P.

Violation of local realism in a high-dimensional two-photon setup with non-integer spiral phase plates

Authors

Oemrawsingh, S. S. R.

Description

We propose a novel setup to investigate the quantum non-locality of orbital angular momentum states living in a high-dimensional Hilbert space. We incorporate non-integer spiral phase plates in spatial analyzers, enabling us to use only two detectors. The resulting setup is somewhat reminiscent of that used to measure polarization entanglement. However, the two-photon states that are produced, are not confined to a 2X2-dimensional Hilbert space, and the setup allows the probing of correlations in a high-dimensional space. For the special case of half-integer spiral phase plates, we predict a violation of the Clauser-Horne-Shimony-Holt version of the Bell inequality (S<=2), that is even stronger than achievable for two qubits (S=2*(2^1/2)), namely S=16/5
7 pages, 4 figures * Fourth author provided analytical solution instead of the previously numerically solved problem. The Klyshko model is no longer used. * Typo in equation 16 corrected