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arXiv · 1203.6692

Experimentally Violating Bell Inequalities Without Complete Reference Frames

Matthew S. Palsson·Joel J. Wallman·Adam J. Bennet·G. J. Pryde
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Abstract

We experimentally demonstrate, using qubits encoded in photon polarization, that if two parties share a single reference direction and use locally orthogonal measurements they will always violate a Bell inequality, up to experimental deficiencies. This contrasts with the standard view of Bell inequalities in which the parties need to share a complete reference frame for their measurements. Furthermore, we experimentally demonstrate that as the reference direction degrades the probability of violating a Bell inequality decreases smoothly to (39.7 +/- 0.1) % in the limiting case that the observers do not share a reference direction. This result promises simplified distribution of entanglement between separated parties, with applications in fundamental investigations of quantum physics and tasks such as quantum communication.

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Matthew S. Palsson, Joel J. Wallman, Adam J. Bennet, G. J. Pryde. 2012-03-30. Experimentally Violating Bell Inequalities Without Complete Reference Frames. https://doi.org/10.1103/physreva.86.032322

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