Angular two-photon interference and angular two-qubit states.

Institute of Optics, University of Rochester, Rochester, New York 14627, USA.
Physical Review Letters (Impact Factor: 7.94). 01/2010; 104(1):010501. DOI:10.1103/PhysRevLett.104.010501
Source: PubMed

ABSTRACT Using angular-position-orbital-angular-momentum entangled photons, we study angular two-photon interference in a scheme in which entangled photons are made to pass through apertures in the form of double angular slits, and using this scheme, we demonstrate an entangled two-qubit state that is based on the angular-position correlations of entangled photons. The entanglement of the two-qubit state is quantified in terms of concurrence. These results provide an additional means for preparing entangled quantum states for use in quantum information protocols.

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